Maternal uniparental disomy 14 syndrome demonstrates prader-willi syndrome-like phenotype.
OBJECTIVE
To delineate the significance of maternal uniparental disomy 14 (upd(14)mat) and related disorders in patients with a Prader-Willi syndrome (PWS)-like phenotype.


METHODS
We examined 78 patients with PWS-like phenotype who lacked molecular defects for PWS. The MEG3 methylation test followed by microsatellite polymorphism analysis of chromosome 14 was performed to detect upd(14)mat or other related abnormalities affecting the 14q32.2-imprinted region.


RESULTS
We identified 4 patients with upd(14)mat and 1 patient with an epimutation in the 14q32.2 imprinted region. Of the 4 patients with upd(14)mat, 3 had full upd(14)mat and 1 was mosaic.


CONCLUSIONS
Upd(14)mat and epimutation of 14q32.2 represent clinically discernible phenotypes and should be designated "upd(14)mat syndrome." This syndrome demonstrates a PWS-like phenotype particularly during infancy. The MEG3 methylation test can detect upd(14)mat syndrome defects and should therefore be performed for all undiagnosed infants with hypotonia.
Hosoki
Kana
K
Department of Pediatrics, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
Kagami
Masayo
M
Tanaka
Touju
T
Kubota
Masaya
M
Kurosawa
Kenji
K
Kato
Mitsuhiro
M
Uetake
Kimiaki
K
Tohyama
Jun
J
Ogata
Tsutomu
T
Saitoh
Shinji
S
D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D002883:Chromosomes, Human, Pair 14 / Q000235:genetics*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D010641:Phenotype; D011218:Prader-Willi Syndrome / Q000175:diagnosis* / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000235:genetics; D011506:Proteins / Q000235:genetics; D062085:RNA, Long Noncoding; D013577:Syndrome; D024182:Uniparental Disomy / Q000175:diagnosis* / Q000235:genetics*; D055815:Young Adult
C498907:MEG3 non-coding RNA, human; D011506:Proteins; D062085:RNA, Long Noncoding