S. Sammalisto

Publications (4)10.9 Total impact

• Source

  Available from: 152.98.160.29

  Article: Linkage of nicotine dependence and smoking behavior on 10q, 7q and 11p in twins with homogeneous genetic background.

  A Loukola, U Broms, H Maunu, E Widén, K Heikkilä, M Siivola, A Salo, M L Pergadia, E Nyman, S Sammalisto, M Perola, A Agrawal, A C Heath, N G Martin, P A F Madden, L Peltonen, J Kaprio
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  ABSTRACT: The significant worldwide health burden introduced by tobacco smoking highlights the importance of studying the genetic determinants of smoking behavior and the key factor sustaining compulsive smoking, that is, nicotine dependence (ND). We have here addressed the genetic background of smoking in a special study sample of twins, harmonized for early life events and specifically ascertained for smoking from the nationwide twin cohort of the genetically unique population of Finland. The twins and their families were carefully examined for extensive phenotype profiles and a genome-wide scan was performed to identify loci behind the smoking status, ND and the comorbid phenotype of ND and alcohol use in 505 individuals from 153 families. We replicated previous linkage findings on 10q (max logarithm of the odds (LOD) 3.12) for a smoker phenotype, and on 7q and 11p (max LOD 2.50, and 2.25, respectively) for the ND phenotype. The loci linked for ND also showed evidence for linkage for the comorbid phenotype. Our study provides confirmatory evidence for the involvement of these genome regions in the genetic etiology of smoking behavior and ND and for the first time associates drinking and smoking to a shared locus on 10q.
  The Pharmacogenomics Journal 07/2008; 8(3):209-19. · 4.54 Impact Factor
• Source

  Available from: nih.gov

  Article: A male-specific quantitative trait locus on 1p21 controlling human stature.

  S Sammalisto, T Hiekkalinna, E Suviolahti, K Sood, A Metzidis, P Pajukanta, H E Lilja, A Soro-Paavonen, M-R Taskinen, T Tuomi, P Almgren, M Orho-Melander, L Groop, L Peltonen, M Perola
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  ABSTRACT: Many genome-wide scans aimed at complex traits have been statistically underpowered due to small sample size. Combining data from several genome-wide screens with comparable quantitative phenotype data should improve statistical power for the localisation of genomic regions contributing to these traits. To perform a genome-wide screen for loci affecting adult stature by combined analysis of four previously performed genome-wide scans. We developed a web based computer tool, Cartographer, for combining genetic marker maps which positions genetic markers accurately using the July 2003 release of the human genome sequence and the deCODE genetic map. Using Cartographer, we combined the primary genotype data from four genome-wide scans and performed variance components (VC) linkage analyses for human stature on the pooled dataset of 1417 individuals from 277 families and performed VC analyses for males and females separately. We found significant linkage to stature on 1p21 (multipoint LOD score 4.25) and suggestive linkages on 9p24 and 18q21 (multipoint LOD scores 2.57 and 2.39, respectively) in males-only analyses. We also found suggestive linkage to 4q35 and 22q13 (multipoint LOD scores 2.18 and 2.85, respectively) when we analysed both females and males and to 13q12 (multipoint LOD score 2.66) in females-only analyses. We strengthened the evidence for linkage to previously reported quantitative trait loci (QTL) for stature and also found significant evidence of a novel male-specific QTL on 1p21. Further investigation of several interesting candidate genes in this region will help towards characterisation of this first sex-specific locus affecting human stature.
  Journal of Medical Genetics 01/2006; 42(12):932-9. · 6.36 Impact Factor
• Article: Linkage of nicotine dependence and smoking behavior on 10q, 7q and 11p in twins with homogeneous genetic background

  A Loukola, U Broms, H. Maunu, E Widen, K. Heikkila, M. Siivola, A Salo, M L Pergadia, E. Nyman, S. Sammalisto, M Perola, A Agrawal, A C Heath, N G Martin, P A Madden, L Peltonen, J Kaprio
  [show abstract] [hide abstract]
  ABSTRACT: The significant worldwide health burden introduced by tobacco smoking highlights the importance of studying the genetic determinants of smoking behavior and the key factor sustaining compulsive smoking, that is, nicotine dependence (ND). We have here addressed the genetic background of smoking in a special study sample of twins, harmonized for early life events and specifically ascertained for smoking from the nationwide twin cohort of the genetically unique population of Finland. The twins and their families were carefully examined for extensive phenotype profiles and a genome-wide scan was performed to identify loci behind the smoking status, ND and the comorbid phenotype of ND and alcohol use in 505 individuals from 153 families. We replicated previous linkage findings on 10q (max logarithm of the odds (LOD) 3.12) for a smoker phenotype, and on 7q and 11p (max LOD 2.50, and 2.25, respectively) for the ND phenotype. The loci linked for ND also showed evidence for linkage for the comorbid phenotype. Our study provides confirmatory evidence for the involvement of these genome regions in the genetic etiology of smoking behavior and ND and for the first time associates drinking and smoking to a shared locus on 10q.The Pharmacogenomics Journal advance online publication, 5 June 2007; doi:10.1038/sj.tpj.6500464.
• Article: Combined genome scans for body stature in 6,602 European twins: Evidence for common Caucasian loci

  M Perola, S. Sammalisto, T Hiekkalinna, N G Martin, P M Visscher, G W Montgomery, B Benyamin, J R Harris, D Boomsma, G Willemsen, [......], K O Kyvik, T I Sorensen, N L Pedersen, P K Magnusson, T D Spector, E Widen, K Silventoinen, J Kaprio, A Palotie, L Peltonen
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  ABSTRACT: Twin cohorts provide a unique advantage for investigations of the role of genetics and environment in the etiology of variation in common complex traits by reducing the variance due to environment, age, and cohort differences. The GenomEUtwin (http://www.genomeutwin.org) consortium consists of eight twin cohorts (Australian, Danish, Dutch, Finnish, Italian, Norwegian, Swedish, and United Kingdom) with the total resource of hundreds of thousands of twin pairs. We performed quantitative trait locus (QTL) analysis of one of the most heritable human complex traits, adult stature (body height) using genome-wide scans performed for 3,817 families (8,450 individuals) derived from twin cohorts from Australia, Denmark, Finland, Netherlands, Sweden, and United Kingdom with an approximate ten-centimorgan microsatellite marker map. The marker maps for different studies differed and they were combined and related to the sequence positions using software developed by us, which is publicly available (https://apps.bioinfo.helsinki.fi/software/cartographer.aspx). Variance component linkage analysis was performed with age, sex, and country of origin as covariates. The covariate adjusted heritability was 81% for stature in the pooled dataset. We found evidence for a major QTL for human stature on 8q21.3 (multipoint logarithm of the odds 3.28), and suggestive evidence for loci on Chromosomes X, 7, and 20. Some evidence of sex heterogeneity was found, however, no obvious female-specific QTLs emerged. Several cohorts contributed to the identified loci, suggesting an evolutionarily old genetic variant having effects on stature in European-based populations. To facilitate the genetic studies of stature we have also set up a website that lists all stature genome scans published and their most significant loci (http://www.genomeutwin.org/stature_gene_map.htm).