Open AccessBreakage in the SNRPN locus in a balanced 46,XY,t(15;19) Prader-Willi syndrome patient
Author(s) -
Yongming Sun,
Robert D. Nicholls,
Merlin G. Butler,
Shinji Saitoh,
Bryan E. Hainline,
Catherine G. Palmer
Publication year - 1996
Publication title -
human molecular genetics online/human molecular genetics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.811
H-Index - 276
eISSN - 1460-2083
pISSN - 0964-6906
DOI - 10.1093/hmg/5.4.517
Subject(s) - biology , exon , genetics , locus (genetics) , angelman syndrome , chromosome 15 , chromosomal translocation , breakpoint , microbiology and biotechnology , gene
A patient with Prader-Willi syndrome (PWS) was found to carry a de novo balanced reciprocal translocation, t(15;19)(q12;q13.41), which disrupted the small nuclear ribonucleoprotein N (SNRPN) locus. The translocation chromosome 15 was found to be paternal in origin. Uniparental disomy and abnormal DNA methylation were ruled out. The translocation breakpoint was found to have occurred between exon 0 (second exon) and 1 (third exon) of the SNRPN locus outside of the SmN open reading frame (ORF), which is intact. The transcriptional activities of ZNF127, IPW, PAR-1, and PAR-5 were detected with RT-PCR from fibroblasts of the patient, suggesting that these genes may not play a significant role in the PWS phenotype in this patient. Transcription from the first two exons and last seven exons of the SNRPN gene was also detected with RT-PCR; however, the complete mRNA (10 exons) was not detected. Thus, the PWS phenotype in the patient is likely to be the result of disruption of the SNRPN locus.