Genomic analysis of partial 21q monosomies with variable phenotypes.

TitleGenomic analysis of partial 21q monosomies with variable phenotypes.
Publication TypeJournal Article
Year of Publication2011
AuthorsRoberson EDO, Wohler ES, Hoover-Fong JE, Lisi E, Stevens EL, Thomas GH, Leonard J, Hamosh A, Pevsner J
JournalEuropean journal of human genetics : EJHG
Volume19
Issue2
Pagination235-8
Date Published2011 Feb
Abstract

Partial monosomy 21 was recently segregated into three regions associated with variable clinical severity. We describe 10 new patients, all examined by single nucleotide polymorphism (SNP) genotyping and G-banded karyotyping. Cohort A consisted of three patients seen in our medical genetics clinics with partial chromosome 21 monosomies. In two of these patients having terminal deletions (21q22.2-ter and 21q22.3-ter), the breakpoints differed by at least 812 Kb of sequence, containing seven RefSeq genes. A third patient had an interstitial hemizygous loss of 16.4 Mb (21q21.1-q22.11). All three patients had relatively mild phenotypes. Cohort B consisted of seven patients with partial chromosome 21 monosomies who had a greater number of dysmorphic features and some major malformations; SNP genotypes were obtained from the Coriell Genetic Cell Repository. We also collected data on partial monsomy 21 cases from the DECIPHER database. This report of 10 new cases of 21q deletion and review of a total of 36 confirms that deletion of the terminal region is associated with a mild phenotype, but suggests that deletion of regions 1 and 2 is compatible with life and have a variable phenotype perhaps relating more to other genetic and environmental variables than to genes in the interval.

DOI10.1097/BRS.0b013e3181e7d675
Alternate JournalEur. J. Hum. Genet.