Maternal isodisomy for 14q21-q24 in a man with diabetes mellitus.
We report a 20-year-old man with maternal uniparental disomy for chromosome 14 (UPD14) and maturity-onset diabetes mellitus (DM). He had pre- and postnatal growth retardation, developed DM at age 20 years without any autoimmune antibodies, and had a mosaic 45,XY,der(14;14)(q10;q10)[129]/46,XY,+14,der(14;14)(q10;q10)[1] karyotype. Allelotyping using microsatellite markers covering the entire 14q indicated segmental maternal isodisomy for 14q21-q24 and maternal heterodisomy of the remaining regions of the chromosome. It is thus tempting to speculate that the segmental isodisomy led to reduction to homozygosity for a mutant gene and thus caused his DM, although the possibility of coincidental occurrence of the two events cannot totally be ruled out. Fluorescence in situ hybridization (FISH) analysis using BAC clone probes revealed that the isodisomic segment did not overlap any known IDDM or NIDDM susceptibility loci on chromosome 14, suggesting a novel locus for a subset of DM at the isodisomic segment.
Department of Human Genetics, Nagasaki University, Japan. d399022y@stcc.nagasaki-u.ac.jp
Tomohiko
T
Kayashima
Masahito
M
Katahira
Naoki
N
Harada
Nobutomo
N
Miwa
Tohru
T
Ohta
Koh-Ichiro
K
Yoshiura
Naomichi
N
Matsumoto
Yoshibumi
Y
Nakane
Yusuke
Y
Nakamura
Tadashi
T
Kajii
Norio
N
Niikawa
Tatsuya
T
Kishino
D000328:Adult; D002883:Chromosomes, Human, Pair 14 / Q000235:genetics*; D003924:Diabetes Mellitus, Type 2 / Q000235:genetics*; D004392:Dwarfism / Q000235:genetics*; D006801:Humans; D008607:Intellectual Disability / Q000235:genetics*; D007621:Karyotyping; D008297:Male; D018895:Microsatellite Repeats; D009030:Mosaicism; D009765:Obesity / Q000235:genetics; D010641:Phenotype; D024182:Uniparental Disomy