Päivi Onkamo

University of Helsinki, Helsinki, Southern Finland Province, Finland

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Publications (41)149.13 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Humans have developed the perception, production and processing of sounds into the art of music. A genetic contribution to these skills of musical aptitude has long been suggested. We performed a genome-wide scan in 76 pedigrees (767 individuals) characterized for the ability to discriminate pitch (SP), duration (ST) and sound patterns (KMT), which are primary capacities for music perception. Using the Bayesian linkage and association approach implemented in program package KELVIN, especially designed for complex pedigrees, several single nucleotide polymorphisms (SNPs) near genes affecting the functions of the auditory pathway and neurocognitive processes were identified. The strongest association was found at 3q21.3 (rs9854612) with combined SP, ST and KMT test scores (COMB). This region is located a few dozen kilobases upstream of the GATA binding protein 2 (GATA2) gene. GATA2 regulates the development of cochlear hair cells and the inferior colliculus (IC), which are important in tonotopic mapping. The highest probability of linkage was obtained for phenotype SP at 4p14, located next to the region harboring the protocadherin 7 gene, PCDH7. Two SNPs rs13146789 and rs13109270 of PCDH7 showed strong association. PCDH7 has been suggested to play a role in cochlear and amygdaloid complexes. Functional class analysis showed that inner ear and schizophrenia-related genes were enriched inside the linked regions. This study is the first to show the importance of auditory pathway genes in musical aptitude.Molecular Psychiatry advance online publication, 11 March 2014; doi:10.1038/mp.2014.8.
    Molecular Psychiatry 03/2014; · 15.15 Impact Factor
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    ABSTRACT: PURPOSE: To analyse lesion components determining retinal sensitivity in microperimetry in eyes with newly diagnosed exudative age-related macular degeneration (AMD). METHODS: Visual acuity, contrast sensitivity, microperimetry, optical coherence tomography (OCT), and fluorescein (FA) and indocyanine green (ICGA) angiographies of 23 eyes of 23 patients were analysed. Central microperimetry grids with 28 test stimulus sites were automatically aligned with three-dimensional OCTs and manually aligned with angiographies. Thicknesses of the neuroretina, neuroepithelial detachment (NED), retinal pigment epithelial (RPE) elevation and subretinal tissue were measured under the 644 microperimetry stimulus sites. Areas of classic and occult choroidal neovascularizations (CNVs), subretinal and intraretinal haemorrhage, and late hyperfluorescence in ICGA were identified. The impact of the lesion components on retinal sensitivity was evaluated with correlation analysis and multivariate modelling. RESULTS: Decreased retinal sensitivity correlated significantly with the presence of CNV, haemorrhage, subretinal tissue and RPE elevation. Out of the OCT parameters, the most important determinant of sensitivity was the thickness of RPE elevation (Spearman's rho, r = -0.202, p < 0.0001). The thicknesses of subretinal tissue (r = -0.168, p < 0.0001) and NED had weaker effects (r = -0.147, p < 0.0001), and the neuroretinal thickness remained nonsignificant. In multivariate modelling, RPE elevation and subretinal tissue in OCT, CNV membranes in angiographies and haemorrhage had the strongest impacts on retinal sensitivity. CONCLUSION: The most important lesion components affecting retinal function were RPE elevation and subretinal tissue in OCT as well as neovascular membranes and haemorrhage in angiographies. NED and neuroretinal thickening remained less significant.
    Acta ophthalmologica 02/2014; 92(1):51-58. · 2.44 Impact Factor
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    ABSTRACT: Purpose To study the association of potential key single-nucleotide polymorphisms with the short-term anatomic response to bevacizumab treatment in exudative age-related macular degeneration (AMD). Methods Clinical data of 96 bevacizumab-treated exudative age-related macular degeneration patients were analyzed retrospectively. Blood DNA was collected. Based on the disappearance of intra- or subretinal fluid in optical coherence tomography, patients were graded as responders, partial responders, or nonresponders after 3 initial treatment visits and a median time of 3.5 months. Representative single-nucleotide polymorphisms of interleukin 8, vascular endothelial growth factor, erythropoietin, complement factor H, complement component C3, and LOC387715 genes were analysed. Results Interleukin 8 promoter polymorphism −251A/T,conferring a more acitve interleuking-8 system, was significantly associated with persisting fluid in optical coherence tomography. The A allele was more frequent in nonresponders than in responders (P = 0.033). In multivariate modeling, the AA genotype of −251A/T (P = 0.043) and occult (P = 0.042) or predominantly classic (P = 0.040) lesions predicted a poorer outcome. Conclusion The interleukin -8 pathway may modulate the early anatomic response to anti-VEGF treatment in AMD. A possible activation of interleukin -8 production in patients may represent a compensatory mechanism to chronic blockade of VEGF signalling in AMD lesions
    Acta ophthalmologica 08/2013; 91(s252). · 2.44 Impact Factor
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    ABSTRACT: Purpose To study the effects of IL-8, VEGF, CFH, complement component C3 and LOC387715 single nucleotide polymorphisms and neovascular lesion characteristics on the response to intravitreal bevacizumab treatment in exudative age-related macular degeneration (AMD). Methods Fifty patients with treatment naïve exudative AMD were recruited to this two-year prospective follow-up study, and treated with bevacizumab on their once-a-month visits when sub- or intraretinal fluid in OCTs, or a new hemorrhage was detected. Visual acuities (VA) and contrast sensitivities (CS) were assessed on every visit, and fluorescein (FA) and indocyanine green (ICGA) angiographies recorded at baseline, and after one and two years of follow-up. Blood samples were collected for genotyping. Results VEGF -2578A/C and CFH Y402H polymorphisms and baseline lesion size in ICGA associated with the number of needed reinjections during the follow-up, and IL-8 -251A/T associated with the disappearance of fluid in OCTs. The alleles A in IL-8 -251A/T, A in VEGF -2578A/C, and C in CFH Y402H had a cumulative effect on the presence of fluid in OCTs. A marked difference existed between patients having 0 - 2 risk alleles compared to those having 3 - 6 risk alleles (P=0.00002). An association was also detected between the VEGF -2578A/C polymorphism and CS gain (P=0.014). During the first year VA change correlated negatively with the number of visits when cystic changes were detected in the OCTs (r=-0.366, P=0.009), but the association did not persist during the second year. Conclusion VEGF -2578A/C, IL-8 -251A/T, and CFH Y402H seem to to affect the persistence of fluid in the macular area during bevacizumab therapy of exudative AMD.
    Acta Ophthalmologica; 08/2013
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    ABSTRACT: PURPOSE:: To study the association of single-nucleotide polymorphisms of interleukin 8, vascular endothelial growth factor, erythropoietin, complement factor H, complement component C3, and LOC387715 genes with the response to bevacizumab treatment in exudative age-related macular degeneration. METHODS:: Clinical records, smoking history, optical coherence tomography, and angiographies of 96 bevacizumab-treated exudative age-related macular degeneration patients were analyzed retrospectively. Blood DNA was collected. Based on the disappearance of intra- or subretinal fluid in optical coherence tomography, patients were graded as responders, partial responders, or nonresponders after 3 initial treatment visits and a median time of 3.5 months. RESULTS:: Interleukin 8 promoter polymorphism -251A/T was significantly associated with persisting fluid in optical coherence tomography. The A allele was more frequent in nonresponders than in responders (P = 0.033). In multivariate modeling, the AA genotype of -251A/T (P = 0.043) and occult (P = 0.042) or predominantly classic (P = 0.040) lesions predicted poorer outcome. Visual acuity change was better in responders than in nonresponders (P = 0.006). Baseline lesion size (P = 0.006) and retinal cysts after the treatment (P < 0.001) correlated with less visual acuity gain. CONCLUSION:: The A allele and the homozygous AA genotype of interleukin 8 -251A/T were associated with anatomical nonresponse to bevacizumab treatment.
    Retina (Philadelphia, Pa.) 04/2013; · 2.93 Impact Factor
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    ABSTRACT: Innate immunity plays a crucial role in the host defense against malaria including Plasmodium falciparum malaria in pregnancy, but the roles of the various underlying genes and mechanisms predisposing to the disease are poorly understood. 98 single-nucletoide polymorphisms were genotyped in a set of 17 functionally related genes of the complement system in 145 primiparous Ghanaian women with placental malaria, defined by placental parasitaemia or malaria pigment, and as a control, in 124 non-affected primiparae. Placental malaria was significantly associated with SNPs in the lectin pathway genes MBL2, MASP2, FCN2 and in properdin. In particular, the main African mannose-binding lectin deficiency variant (MBL2*G57E, rs1800451) increased the odds of placental malaria (OR 1.6; permuted p-value 0.014). In contrast, a common MASP2 mutation (R439H, rs12085877), which reduces the activity of MBL-MASP2 complexes occurred in 33% of non-affected women and in 22% primiparae with placental malaria (OR 0.55, permuted p-value 0.020). Excessive complement activation is of importance in the pathogenesis of placental malaria by mediating inflammation, coagulation, and endothelial dysfunction. Mutated MBL and MASP2 proteins could have direct intrinsic effects on the susceptibility to placental malaria, in addition to their roles in regulation of downstream complement activation.
    Malaria Journal 03/2012; 11:61. · 3.49 Impact Factor
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    ABSTRACT: Otitis media is a multifactorial disease where genetic background may have an important role. For genome-wide association studies, it is important to understand the degree of heritability. The objective of this study was to estimate the heritability of recurrent acute otitis media and chronic otitis media with effusion. Children operated because of recurrent or chronic otitis media at the Helsinki University Central Hospital, Finland, as well as their families were recruited during 2008-2009. A cohort of 2436 subjects was enrolled consisting of 1279 children and their parents. The study subjects answered a questionnaire concerning their otitis media history and treatment, as well as tobacco exposure, allergy and asthma history. Heritability estimates were calculated for recurrent acute, chronic and any episodes of otitis media using software especially designed for estimating heritability in family cohorts. Altogether 901 subjects suffered from recurrent otitis media and 559 from chronic otitis media with effusion. The heritability estimates in our cohort were 38.5% for recurrent (P=7.3 × 10(-9)), 22.1% for chronic (P=4.6 × 10(-3)) and 47.8% for any otitis media (P=1.5 × 10(-11)). Our results demonstrate a moderately strong and statistically significant genetic component for both recurrent acute otitis media and chronic otitis media with effusion. These results highlight the importance of unraveling the genetic factors for otitis media that are still poorly known.
    International journal of pediatric otorhinolaryngology 01/2012; 76(1):41-4. · 0.85 Impact Factor
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    ABSTRACT: Music is listened in all cultures. We hypothesize that willingness to produce and perceive sound and music is social communication that needs musical aptitude. Here, listening to music was surveyed using a web-based questionnaire and musical aptitude using the auditory structuring ability test (Karma Music test) and Carl Seashores tests for pitch and for time. Three highly polymorphic microsatellite markers (RS3, RS1 and AVR) of the arginine vasopressin receptor 1A (AVPR1A) gene, previously associated with social communication and attachment, were genotyped and analyzed in 31 Finnish families (n=437 members) using family-based association analysis. A positive association between the AVPR1A haplotype (RS1 and AVR) and active current listening to music (permuted P=0.0019) was observed. Other AVPR1A haplotype (RS3 and AVR) showed association with lifelong active listening to music (permuted P=0.0022). In addition to AVPR1A, two polymorphisms (5-HTTLPR and variable number of tandem repeat) of human serotonin transporter gene (SLC6A4), a candidate gene for many neuropsychiatric disorders and previously associated with emotional processing, were analyzed. No association between listening to music and the polymorphisms of SLC6A4 were detected. The results suggest that willingness to listen to music is related to neurobiological pathways affecting social affiliation and communication.
    Journal of Human Genetics 02/2011; 56(4):324-9. · 2.37 Impact Factor
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    ABSTRACT: Four genes, DYX1C1, ROBO1, DCDC2 and KIAA0319 have been studied both genetically and functionally as candidate genes for developmental dyslexia, a common learning disability in children. The identification of novel genes is crucial to better understand the molecular pathways affected in dyslectic individuals. Here, we report results from a fine-mapping approach involving linkage and association analysis in Finnish and German dyslexic cohorts. We restrict a candidate region to 0.3 Mb on chromosome 7q33. This region harbours the gene diacylglycerol kinase, iota (DGKI) which contains overlapping haplotypes associated with dyslexia in both Finnish and German sample sets.
    Behavior Genetics 01/2011; 41(1):134-40. · 2.61 Impact Factor
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    ABSTRACT: Autism spectrum disorders (ASD) often show obsessive repetitive symptoms that are characteristic to obsessive-compulsive disorder (OCD). Aberrant glutamate function has been suggested to a risk for both ASDs and OCD. Considering the common metabolic pathway and recent results from association studies both in OCD and ASDs, a question, whether there is common molecular background in ASDs and OCD, was raised. Ten single nucleotide polymorphisms (SNPs) at 9p24 and 11p12-p13 containing glutamate transporter genes SLC1A1 and SLC1A2 and their neighboring regions in 175 patients with ASDs and 216 controls of Finnish origin were analyzed using real-time-PCR or direct sequencing. The strongest association was detected with rs1340513 in the JMJD2C gene at 9p24.1 (P=0.007; corrected P=0.011) that is the same SNP associated with infantile autism (P=0.0007) in the autism genome project consortium (2007). No association was detected at 11p12-p13 with ASD. Interestingly, the strongest association in OCD has been found at rs301443 (P=0.000067) residing between SLC1A1 and JMJD2C at 9p24. In summary, our results give evidence for a possible common locus for OCD and ASDs at 9p24. We speculate that the area may represent a special candidate region for obsessive repetitive symptoms in ASDs.
    Psychiatric genetics 06/2010; 20(3):102-8. · 2.33 Impact Factor
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    ABSTRACT: Several variants in the complement cascade genes (complement factor H [CFH], C2, C3, CFB, and Serping1) have been reported to associate with age-related macular degeneration (AMD). Of these, a member of the complement alternative pathway, CFH, represents the highest risk. As properdin (P) is also an important protein in this pathway, we analysed whether variants in the properdin gene (CFP) at Xp11.4 are associated with AMD. Ten exons of CFP were sequenced in a total of 222 Finnish patients with AMD (150 sporadic cases and 72 familial cases). The controls were 86 age-matched non-AMD patients with no large drusen and no or minimal focal pigmentary abnormalities. A total of four single nucleotide polymorphisms (SNPs) were detected in CFP, three of them infrequent (in 5 patients and controls in total). The fourth SNP, rs1048118 in exon 10, was more frequent, but was not associated with AMD, either alone (p=0.33) or in conjunction with other risk factors. Thus, CFP does not seem to confer any risk for AMD.
    Molecular Immunology 03/2010; 47(6):1334-6. · 2.65 Impact Factor
  • Molecular Immunology - MOL IMMUNOL. 01/2010; 47(13):2216-2216.
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    ABSTRACT: In this study, three single-nucleotide polymorphisms (SNPs) on the lysyl oxidase-like 1 (LOXL1) gene associated with exfoliation syndrome (XFS) and exfoliation glaucoma (XFG) were investigated in the Finnish population. A case-control study of 59 sporadic patients with XFS, 82 with XFG, 71 with primary open-angle glaucoma (POAG) and 26 individuals without these disorders from the southern Finnish population, and a family study of an extended family with 28 patients with XFS or XFG and 92 unaffected relatives from Kökar islands, Southwestern Finnish archipelago, were conducted. Anonymous blood donors (n=404) were studied as population-based controls. Three SNPs, rs1048661 (R141L), rs3825942 (G153D) and rs2165241, of the LOXL1 gene were genotyped by PCR sequencing. Association and linkage analyses were carried out. In both case-control and family materials, significant association for allele G of rs1048661 (P=2.65 x 10(-5); P=0.0007), allele G of rs3825942 (P=2.24 x 10(-8); P=0.49) and allele T of rs2165241 (P=2.62 x 10(-13); P<0.0001) was found in XFS/XFG. However, linkage was not observed for LOXL1 risk alleles. The corresponding three-locus haplotype GGT increased the risk of XFS/ XFG nearly 15-fold relative to low-risk haplotype GAC (odds ratio (OR): 14.9, P=1.6 x 10(-16)). In conclusion, the earlier reported polymorphisms of the LOXL1 gene showed significant association also in the Finnish population.
    Journal of Human Genetics 04/2009; 54(5):289-97. · 2.37 Impact Factor
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    ABSTRACT: Systemic lupus erythematosus (SLE) is a complex autoimmune disorder with multiple susceptibility genes. We have previously reported suggestive linkage to the chromosomal region 14q21-q23 in Finnish SLE families. Genetic fine mapping of this region in the same family material, together with a large collection of parent affected trios from UK and two independent case-control cohorts from Finland and Sweden, indicated that a novel uncharacterized gene, MAMDC1 (MAM domain containing glycosylphosphatidylinositol anchor 2, also known as MDGA2, MIM 611128), represents a putative susceptibility gene for SLE. In a combined analysis of the whole dataset, significant evidence of association was detected for the MAMDC1 intronic single nucleotide polymorphisms (SNP) rs961616 (P -value = 0.001, Odds Ratio (OR) = 1.292, 95% CI 1.103-1.513) and rs2297926 (P -value = 0.003, OR = 1.349, 95% CI 1.109-1.640). By Northern blot, real-time PCR (qRT-PCR) and immunohistochemical (IHC) analyses, we show that MAMDC1 is expressed in several tissues and cell types, and that the corresponding mRNA is up-regulated by the pro-inflammatory cytokines tumour necrosis factor alpha (TNF-alpha) and interferon gamma (IFN-gamma) in THP-1 monocytes. Based on its homology to known proteins with similar structure, MAMDC1 appears to be a novel member of the adhesion molecules of the immunoglobulin superfamily (IgCAM), which is involved in cell adhesion, migration, and recruitment to inflammatory sites. Remarkably, some IgCAMs have been shown to interact with ITGAM, the product of another SLE susceptibility gene recently discovered in two independent genome wide association (GWA) scans. Further studies focused on MAMDC1 and other molecules involved in these pathways might thus provide new insight into the pathogenesis of SLE.
    PLoS ONE 01/2009; 4(12):e8037. · 3.53 Impact Factor
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    ABSTRACT: Artistic creativity forms the basis of music culture and music industry. Composing, improvising and arranging music are complex creative functions of the human brain, which biological value remains unknown. We hypothesized that practicing music is social communication that needs musical aptitude and even creativity in music. In order to understand the neurobiological basis of music in human evolution and communication we analyzed polymorphisms of the arginine vasopressin receptor 1A (AVPR1A), serotonin transporter (SLC6A4), catecol-O-methyltranferase (COMT), dopamin receptor D2 (DRD2) and tyrosine hydroxylase 1 (TPH1), genes associated with social bonding and cognitive functions in 19 Finnish families (n = 343 members) with professional musicians and/or active amateurs. All family members were tested for musical aptitude using the auditory structuring ability test (Karma Music test; KMT) and Carl Seashores tests for pitch (SP) and for time (ST). Data on creativity in music (composing, improvising and/or arranging music) was surveyed using a web-based questionnaire. Here we show for the first time that creative functions in music have a strong genetic component (h(2) = .84; composing h(2) = .40; arranging h(2) = .46; improvising h(2) = .62) in Finnish multigenerational families. We also show that high music test scores are significantly associated with creative functions in music (p<.0001). We discovered an overall haplotype association with AVPR1A gene (markers RS1 and RS3) and KMT (p = 0.0008; corrected p = 0.00002), SP (p = 0.0261; corrected p = 0.0072) and combined music test scores (COMB) (p = 0.0056; corrected p = 0.0006). AVPR1A haplotype AVR+RS1 further suggested a positive association with ST (p = 0.0038; corrected p = 0.00184) and COMB (p = 0.0083; corrected p = 0.0040) using haplotype-based association test HBAT. The results suggest that the neurobiology of music perception and production is likely to be related to the pathways affecting intrinsic attachment behavior.
    PLoS ONE 01/2009; 4(5):e5534. · 3.53 Impact Factor
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    ABSTRACT: The number of persons over 70 years of age with advanced age-related macular degeneration in Finland can be estimated to be approximately 50,000. Milder forms are additionally present in a considerably larger group. Smoking and age are undisputed non-genetic risk factors of age-related macular degeneration. Of the genetic factors, polymorphisms of the complement factor H (CFH) and LOC387715 genes have a strong impact on the risk of developing the disease, whereas alleles of the C3, CFB, and the C1 inhibitor SERPING1 genes of the complement system exhibit only minor effects.
    Duodecim; lääketieteellinen aikakauskirja 01/2009; 125(21):2360-4.
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    ABSTRACT: Variants in the complement cascade genes and the LOC387715/HTRA1, have been widely reported to associate with age-related macular degeneration (AMD), the most common cause of visual impairment in industrialized countries. We investigated the association between the LOC387715 A69S and complement component C3 R102G risk alleles in the Finnish case-control material and found a significant association with both variants (OR 2.98, p = 3.75 x 10(-9); non-AMD controls and OR 2.79, p = 2.78 x 10(-19), blood donor controls and OR 1.83, p = 0.008; non-AMD controls and OR 1.39, p = 0.039; blood donor controls), respectively. Previously, we have shown a strong association between complement factor H (CFH) Y402H and AMD in the Finnish population. A carrier of at least one risk allele in each of the three susceptibility loci (LOC387715, C3, CFH) had an 18-fold risk of AMD when compared to a non-carrier homozygote in all three loci. A tentative gene-gene interaction between the two major AMD-associated loci, LOC387715 and CFH, was found in this study using a multiplicative (logistic regression) model, a synergy index (departure-from-additivity model) and the mutual information method (MI), suggesting that a common causative pathway may exist for these genes. Smoking (ever vs. never) exerted an extra risk for AMD, but somewhat surprisingly, only in connection with other factors such as sex and the C3 genotype. Population attributable risks (PAR) for the CFH, LOC387715 and C3 variants were 58.2%, 51.4% and 5.8%, respectively, the summary PAR for the three variants being 65.4%. Evidence for gene-gene interaction between two major AMD associated loci CFH and LOC387715 was obtained using three methods, logistic regression, a synergy index and the mutual information (MI) index.
    PLoS ONE 02/2008; 3(12):e3833. · 3.53 Impact Factor
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    ABSTRACT: Our objective was to characterize clinical features, laboratory findings, concomitant autoimmune diseases, and smoking habits of lupus erythematosus subgroups in genetically homogeneous patients from two Dermatology Departments of Finnish University hospitals. One hundred and seventy eight discoid lupus erythematosus, 55 subacute cutaneous lupus erythematosus, and 77 systemic lupus erythematosus patients were enrolled using patients' charts from institutional database (1995-2006) and during routine control visits. Clustering analysis was performed to reveal natural groupings. Smoking at the onset of disease was significantly more common in all subgroups (57% for discoid lupus erythematosus, 35% for subacute cutaneous lupus erythematosus, and 34% for systemic lupus erythematosus) compared with the age/gender-matched prevalence in the Finnish population, suggesting smoking to be a trigger factor for cutaneous lupus. Leukopenia (38%) and lymphopenia (52%) were observed more often in patients with systemic lupus erythematosus than reported previously. Photosensitivity characterized all groups, especially patients with subacute cutaneous lupus erythematosus (87%). Of the autoimmune diseases, Sjögren's syndrome was the most common (22% of patients with systemic lupus erythematosus), followed by autoimmune thyroid disease (13% of patients with subacute cutaneous lupus erythematosus). The clustering analysis showed environmental factors (smoking) to be more involved in disease development in discoid lupus erythematosus, whereas immunological factors were more significant in initiating systemic lupus erythematosus. The high prevalence of autoimmune thyroid disease, together with photosensitivity, and the clustering profiles suggest that lupus erythematosus subtypes, especially discoid lupus erythematosus, are heterogeneic in their pathomechanisms.
    Lupus 02/2008; 17(4):337-47. · 2.78 Impact Factor
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    ABSTRACT: DYX3, a locus for dyslexia, resides on chromosome 2p11-p15. We have refined its location on 2p12 to a 157 kb region in two rounds of linkage disequilibrium (LD) mapping in a set of Finnish families. The observed association was replicated in an independent set of 251 German families. Two overlapping risk haplotypes spanning 16 kb were identified in both sample sets separately as well as in a joint analysis. In the German sample set, the odds ratio for the most significantly associated haplotype increased with dyslexia severity from 2.2 to 5.2. The risk haplotypes are located in an intergenic region between FLJ13391 and MRPL19/C2ORF3. As no novel genes could be cloned from this region, we hypothesized that the risk haplotypes might affect long-distance regulatory elements and characterized the three known genes. MRPL19 and C2ORF3 are in strong LD and were highly co-expressed across a panel of tissues from regions of adult human brain. The expression of MRPL19 and C2ORF3, but not FLJ13391, were also correlated with the four dyslexia candidate genes identified so far (DYX1C1, ROBO1, DCDC2 and KIAA0319). Although several non-synonymous changes were identified in MRPL19 and C2ORF3, none of them significantly associated with dyslexia. However, heterozygous carriers of the risk haplotype showed significantly attenuated expression of both MRPL19 and C2ORF3, as compared with non-carriers. Analysis of C2ORF3 orthologues in four non-human primates suggested different evolutionary rates for primates when compared with the out-group. In conclusion, our data support MRPL19 and C2ORF3 as candidate susceptibility genes for DYX3.
    Human Molecular Genetics 04/2007; 16(6):667-77. · 7.69 Impact Factor
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    ABSTRACT: The PSORS1 locus is the consistently replicated genetic risk factor for psoriasis. Clinical associations with the main marker allele of PSORS1, HLA-Cw6, have been addressed in a number of studies, but clinical associations have not been used as a way to distinguish the effects of the neighbouring candidate genes in PSORS1. Our results show that HLA-Cw6 and CCHCR1 risk allele associations with clinical features of psoriasis are predictably highly similar in a Finnish nationwide cohort of 379 psoriasis patients. The clinical profiling of a small group of patients (n=34) who were HLA-Cw6- but CCHCR1*WWCC positive suggested that no great differences existed between them and HCR-Cw6- patients. HCR+ genotype (as well as Cw6+ genotype) correlated for the first time positively with female sex and, in contrast with previous studies, negatively with disease severity. Presence of psoriatic arthritis was more pronounced in HCR-psoriasis (as well as in Cw6- psoriasis). Clinical profiling may be a useful approach to distinguishing genetic effects of candidate genes even within a locus in sufficiently large cohorts.
    Acta Dermato Venereologica 02/2007; 87(2):127-134. · 3.49 Impact Factor

Publication Stats

977 Citations
149.13 Total Impact Points

Institutions

  • 1999–2014
    • University of Helsinki
      • • Department of Biological and Environmental Sciences
      • • Department of Biosciences
      • • Department of Bacteriology and Immunology
      • • Department of Medical Genetics
      • • Department of Ophthalmology
      • • Department of Computer Science
      Helsinki, Southern Finland Province, Finland
  • 2002–2009
    • Karolinska Institutet
      • Institutionen för biovetenskaper och näringslära
      Solna, Stockholm, Sweden
  • 2006
    • Karolinska University Hospital
      Tukholma, Stockholm, Sweden
  • 2004
    • Helsinki Institute for Information Technology HIIT
      Helsinki, Southern Finland Province, Finland
  • 2000
    • Nokia Research Center (NRC)
      Helsinki, Southern Finland Province, Finland
    • National Public Health Institute
      Helsinki, Southern Finland Province, Finland