Psychiatric syndromes in individuals with chromosome 18 abnormalities

Department of Psychiatry, South Texas Psychiatric Genetics Research Center, University of Texas Health Science Center at San Antonio, 454 Soledad, Suite 200, San Antonio, TX 78205, USA.
American Journal of Medical Genetics Part B Neuropsychiatric Genetics (Impact Factor: 3.27). 01/2009; 153B(3):837-45. DOI: 10.1002/ajmg.b.31047
Source: PubMed

ABSTRACT Chromosome 18 abnormalities are associated with a range of physical abnormalities such as short stature and hearing impairments. Psychiatric manifestations have also been observed. This study focuses on the presentations of psychiatric syndromes as they relate to specific chromosomal abnormalities of chromosome 18. Twenty-five subjects (13 with an 18q deletion, 9 with 18p tetrasomy, and 3 with an 18p deletion), were interviewed by psychiatrists (blind to specific chromosomal abnormality) using the DIGS (subjects 18 and older) or KSADS-PL (subjects under 18). A consensus best estimation diagnostic process was employed to determine psychiatric syndromes. Oligonucleotide Array Comparative Genomic Hybridization (Agilent Technologies) was utilized to define specific regions of chromosome 18 that were deleted or duplicated. These data were further analyzed to determine critical regions of the chromosome as they relate to phenotypic manifestations in these subjects. 58.3% of the chromosome 18q- deletion subjects had depressive symptoms, 58.3% had anxiety symptoms, 25% had manic symptoms, and 25% had psychotic symptoms. 66.6% of the chromosome 18p- deletion subjects had anxiety symptoms, and none had depressive, manic, or psychotic symptoms. Fifty percent of the chromosome 18p tetrasomy subjects had anxiety symptoms, 12.5% had psychotic symptoms, and 12.5% had a mood disorder. All three chromosomal disorders were associated with high anxiety rates. Psychotic, manic and depressive disorders were seen mostly in 18q- subjects and this may be helpful in narrowing regions for candidate genes for these psychiatric conditions.

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    ABSTRACT: Die Tetrasomie 18p ist eine seltene chromosomale Störung (1:140.000 Lebendgeborene), die Mädchen und Jungen gleichermaßen betrifft und genetisch determiniert oder als Neumutation (De-novo-Mutation) auftreten kann. Die phänotypischen Merkmale entstehen durch ein kleines metazentrisches Markerchromosom, ein Isochromosom 18p. Zu den in ihrem Ausmaß variablen klinischen Manifestationen können u. a. Spracherwerbsbehinderungen, Epilepsie, vermindertes Längenwachstum, anfänglich generalisierte Muskelhypotonie mit nachfolgenden Spastiken der unteren Extremitäten, die das Stehen und Gehen erschweren, Fehlanlagen des urogenitalen Systems und kongenitale Herzfehler gehören. Auch wenn Hörstörungen in einigen Fällen beobachtet wurden, ist eine sensorineurale Störung bei der Tetrasomie 18p bisher nicht als ein syndromtypisches Symptom beschrieben worden. Im vorliegenden Fall berichten wir über einen Jungen mit einer Tetrasomie 18p. Neben der für dieses Syndrom typischen psychomotorischen Retardierung mit Muskelhypotonie und fazialen Dysmorphien bestand beidseits eine mittel- bis hochgradige Innenohrschwerhörigkeit. Bei Kindern mit chromosomalen Störungen sollte das Hörvermögen frühzeitig mit einer Hirnstammaudiometrie (BERA, „brainstem-evoked response audiometry“) überprüft werden. Durch psychomotorische Retardierung maskierte Schwerhörigkeiten können so frühzeitig erkannt und behandelt werden. Außerdem ist eine humangenetische Diagnostik bei Kindern mit Entwicklungsauffälligkeiten und Dysmorphiezeichen zur Klärung der Ätiologie wünschenswert.
    HNO 10/2012; 60(10). DOI:10.1007/s00106-011-2459-9 · 0.54 Impact Factor
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    ABSTRACT: Background Recent development of MLPA (Multiplex-Ligation-dependent Probe Amplification, MRC-Holland) and microarray technology allows detection of a wide range of new submicroscopic abnormalities. Publishing new cases and case reviews associated with both clinical abnormalities and a normal phenotype is of great value. Findings/results We report on two phenotypically normal foetuses carrying a maternally-inherited interstitial submicroscopic abnormality of chromosome 18p11.32. Both abnormalities were found with the aneuploidy MLPA kit P095 during rapid aneuploidy detection, which was offered along with conventional karyotyping. Foetus 1 and its mother have a 1,7 Mb deletion and foetus 2 and its mother have a 1,9 Mb duplication. In both cases normal babies were born. We used the HumanCytoSNP-12 array of Illumina to visualize the CNVs and map the breakpoints. Conclusions We suggest that a CNV at 18p11.32 (528,050-2,337,486) may represent a new benign euchromatic variant.
    Molecular Cytogenetics 12/2011; 4(1):27. DOI:10.1186/1755-8166-4-27 · 2.66 Impact Factor
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    ABSTRACT: Background: Tetrasomy 18p is a very rare chromosomal disorder and is the result of a spontaneous mutation early in embryonic development in most of the cases. This condition is characterised by the presence of a supernumerary 18p isochromosome (i(18p)) in all or some cells of the affected individual. It has a prevalence of 1/180000 live births and affects both genders equally.Materials and methods: In this paper we report a de novo tetrasomy 18p in a 3 months old female dysmorphic child. The clinical features were distinctive with a particular facies, strabismus, microcephaly, growth delay, neonatal hypertonia and talipes varus. An additional small metacentric marker chromosome has been identified after standard cytogenetic analysis, without recognized parental origin of the supplementary genetic material. The child's parents were also tested and their karyotype results were normal. The characterization of the marker chromosome was performed in our genetics laboratory using conventional cytogenetic methods and Fluorescence in Situ Hybridization (FISH) analysis. Also, our patient was compared with other published cases with the same diagnosis.Conclusion: Cytogenetic investigation is an essential step towards the accurate diagnosis of individuals with clinical suspicion of a genetic anomaly. Also, this type of investigation could offer critical information to the practitioner for prognosis of patient and the correct appreciation of the recurrence risk of a certain genetic condition.With current advances in preventive and interventional procedures, patients with rare chromosomal disorders can live longer. Therefore, proper medical and behavioural management of each case is important for the enhancement of the quality of life for the patients and their families.
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