Molecular mapping of twenty-four features of Down syndrome on chromosome 21

JM Delabar, D Theophile, Z Rahmani… - European Journal of …, 1993 - karger.com
JM Delabar, D Theophile, Z Rahmani, Z Chettouh, JL Blouin, M Prieur, B Noel, PM Sinet
European Journal of Human Genetics, 1993karger.com
Abstract To determine which regions of chromosome 21 are involved in the pathogenesis of
specific features of Down syndrome, we analysed, phenotypically and molecularly, 10
patients with partial trisomy 21. Six minimal regions for 24 features were defined by
genotype-phenotype correlations. Nineteen of these features could be assigned to just 2
regions: short stature, joint hyperlaxity, hypotonia, major contribution to mental retardation
and 9 anomalies of the face, hand and foot to the region D21S55, or Down syndrome …
Abstract
Abstract To determine which regions of chromosome 21 are involved in the pathogenesis of specific features of Down syndrome, we analysed, phenotypically and molecularly, 10 patients with partial trisomy 21. Six minimal regions for 24 features were defined by genotype-phenotype correlations. Nineteen of these features could be assigned to just 2 regions: short stature,joint hyperlaxity, hypotonia, major contribution to mental retardation and 9 anomalies of the face, hand and foot to the region D21S55, or Down syndrome chromosome region(DCR), located on q22.2 or very proximal q22.3, and spanning 0.4-3 Mb; 6 facial and dermatoglyphic anomalies to the region D21S55-MX1, including the DCR and spanning a maximum of 6 Mb on q22.2 and part of q22.3. Thus, the complex phenotype that constitutes Down syndrome may in large part simply result from the overdosage of only one or a few genes within the DCR and/or region D21S55-MX1.
Karger