Molecular definition of the chromosome 7 deletion in Williams syndrome and parent-of-origin effects on growth

Journal Article · Tue Oct 01 04:00:00 EDT 1996 · American Journal of Human Genetics

OSTI ID:476748

Perez Jurado, L A; Peoples, R; Francke, U ^[1]

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1. Stanford Univ. School of Medicine, CA (United States); and others

Williams syndrome (WS) is a developmental disorder with variable phenotypic expression associated, in most cases, with a hemizygous deletion of part of chromosomal band 7q11.23 that includes the elastin gene (ELN). We have investigated the frequency and size of the deletions, determined the parental origin, and correlated the molecular results with the clinical findings in 65 WS patients. Hemizygosity at the ELN locus was established by typing of two intragenic polymorphisms, quantitative Southern analysis, and/or FISH. Polymorphic markers covering the deletion and flanking regions were ordered by a combination of genetic and physical mapping. Genotyping of WS patients and available parents for 13 polymorphisms revealed that of 65 clinically defined WS patients, 61 (94%) had a deletion of the ELN locus and were also hemizygous (or non-informative) at loci D7S489B, D7S2476, D7S613, D7S2472, and D7S1870. None of the four patients without ELN deletion was hemizygous at any of the polymorphic loci studied. All patients were heterozygous (or noninformative) for centromeric (D7S1816, D7S1483, and D7S653) and telomeric (D7S489A, D7S675, and D7S669) flanking loci. The genetic distance between the most-centromeric deleted locus, D7S489B, and the most-telomeric one, D7S1870, is 2 cM. The breakpoints cluster at {approximately}1 cM to either side of ELN. In 39 families informative for parental origin, all deletions were de novo, and 18 were paternally and 21 maternally derived. Comparison of clinical data, collected in a standardized quantifiable format, revealed significantly more severe growth retardation and microcephaly in the maternal deletion group. An imprinted locus, silent on the paternal chromosome and contributing to statural growth, may be affected by the deletion. 53 refs., 5 figs., 2 tabs.

• OSTI ID: 476748
• Journal Information: American Journal of Human Genetics, Journal Name: American Journal of Human Genetics Journal Issue: 4 Vol. 59; ISSN AJHGAG; ISSN 0002-9297
• Country of Publication: United States
• Language: English

Related Subjects

55 BIOLOGY AND MEDICINE
BASIC STUDIES
BIOLOGICAL MARKERS
CHROMOSOMAL ABERRATIONS
DNA HYBRIDIZATION
FLUORESCENCE
GENE MUTATIONS
GENES
GENETIC MAPPING
GENETICS
GENOTYPE
GROWTH
HEREDITARY DISEASES
HUMAN CHROMOSOME 7
L CODES
MENTAL DISORDERS
MUTATION FREQUENCY
PATIENTS
PHENOTYPE
STATISTICS