The origin of trisomy 13.
Trisomy 13 is one of the most common trisomies in clinically recognized pregnancies and one of the few trisomies identified in liveborns, yet relatively little is known about the errors that lead to trisomy 13. Accordingly, we initiated studies to investigate the origin of the extra chromosome in 78 cases of trisomy 13. Our results indicate that the majority of cases (>91%) are maternal in origin and, similar to other autosomal trisomies, the extra chromosome is typically due to errors in meiosis I. Surprisingly, however, a large number of errors also occur during maternal meiosis II ( approximately 37%), distinguishing trisomy 13 from other acrocentric and most nonacrocentric chromosomes. As with other trisomies, failure to recombine is an important contributor to nondisjunction of chromosome 13.
Hall
Heather E
HE
Center for Reproductive Biology and School of Molecular Biosciences, Washington State University, Pullman, Washington 99164-4660, USA.
Chan
E Ricky
ER
Collins
Andrew
A
Judis
LuAnn
L
Shirley
Sofia
S
Surti
Urvashi
U
Hoffner
Lori
L
Cockwell
Annette E
AE
Jacobs
Patricia A
PA
Hassold
Terry J
TJ
D002874:Chromosome Mapping; D002882:Chromosomes, Human, Pair 13; D005260:Female; D008040:Genetic Linkage; D006801:Humans; D009630:Nondisjunction, Genetic; D011995:Recombination, Genetic; D014314:Trisomy