Is there a higher incidence of maternal uniparental disomy 14 [upd(14)mat]? Detection of 10 new patients by methylation-specific PCR.
Maternal uniparental disomy for chromosome 14 [upd(14)mat] is associated with a characteristic phenotype including pre- and postnatal growth retardation, muscular hypotonia, feeding problems, motor delay, small hands and feet, precocious puberty and truncal obesity. Patients with upd(14)mat show features overlapping with Prader-Willi syndrome (PWS) and are probably underdiagnosed. Maternal upd(14) is frequently described in carriers of a Robertsonian translocation involving chromosome 14, but is also found in patients with a normal karyotype. Based on the above mentioned criteria we have identified six patients with upd(14)mat including two patients with a normal karyotype, one patient with a de novo Robertsonian translocation (14;21), one patient with a familial Robertsonian translocation (13;14) and two patients with a marker chromosome. In addition, we analyzed a cohort of 33 patients with low birth weight, feeding difficulties and consecutive obesity in whom PWS had been excluded by methylation analysis of SNRPN. In four of these patients (12%) we detected upd(14)mat. For rapid testing of upd(14)mat we analyzed the methylation status of the imprinted MEG3 locus. In conclusion, we recommend considering upd(14)mat in patients with low birth weight, growth retardation, neonatal feeding problems, muscular hypotonia, motor delay, precocious puberty and truncal obesity as well as in patients with a PWS like phenotype presenting with low birth weight, feeding difficulties and obesity.
Mitter
Diana
D
Institut für Humangenetik, Universitätsklinikum Essen, Essen, Germany.
Buiting
Karin
K
von Eggeling
Ferdinand
F
Kuechler
Alma
A
Liehr
Thomas
T
Mau-Holzmann
Ulrike Angelika
UA
Prott
Eva-Christina
EC
Wieczorek
Dagmar
D
Gillessen-Kaesbach
Gabriele
G
D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D002883:Chromosomes, Human, Pair 14 / Q000235:genetics*; D003582:Cytogenetics; D019175:DNA Methylation; D005260:Female; D006801:Humans; D007223:Infant; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D008297:Male; D018895:Microsatellite Repeats; D009765:Obesity / Q000235:genetics; D010641:Phenotype; D016133:Polymerase Chain Reaction; D011218:Prader-Willi Syndrome / Q000235:genetics; D011247:Pregnancy; D011506:Proteins / Q000235:genetics; D062085:RNA, Long Noncoding; D014178:Translocation, Genetic; D024182:Uniparental Disomy
C498907:MEG3 non-coding RNA, human; D011506:Proteins; D062085:RNA, Long Noncoding