Chinese Siblings with Prader-Willi Syndrome Inherited from Their Paternal Grandmother

Background: Prader-Willi syndrome (PWS) is a complex neurobehavioral disorder causedby failure of expression of paternally inherited genes in the PWS region of chromosome 15.Case characteristics: Two siblings who both met the inclusion criteria for clinical diagnosisof PWS during neonatal period. Outcome: Molecular genetic analysis demonstrated a 417-kb microdeletion within the 15q11.2 region inherited from siblings’ paternal grandmother,involving key genes of PWS, except for UBE3A, which may explain why their father andpaternal grandmother had a normal phenotype. Conclusion: The findings may be helpfulfor better understanding of the underlying mechanism of this rare imprinting defect

CAG Repeat Expansions in the Patients with Mood Disorder / 신경정신의학

OBJECTIVES: The genetic facotrs have been suggested for the etiology of mood disorders but the mode of inheritance is complex. Increased severity and an earlier onset of the bipolar and major depressive disorder over generations within families(Anticipation) were reported. In order to test the hypothesis that trinucleotide repeat expansions underlie the genetic basis of Bipolar and major depressive disorders, we have analyzed the extent of CAG reapeats in genomic DNA from mood disorder patients. METHODS: 55 bipolar disorder, 67 major depressive disorder patients were recruited according to the DSM-III-R criteria. 89 normal controls were recruited from the medical personnel, students and the visitors to the health services center who had no history of psychiatric illness and show normal profile of MMPI. The genomic DNA of patients and controls was analyzed by use of the(CTG) 17 oligonucleotide and the repeat expansion detection(RED) method. The Mann-Whitney U test was used to compare the distribution of the number of CAG repeats among the groups. RESULTS: when the bipolar disorder, major depressive disorder patients were compared with the control group, no significant differences were observed. CONCLUSION: Our results do not support the hypothesis that expanding CAG repeats are causing the observed genetic anticipation in bipolar disorders and major depressive disorders.