X-linked duplication copy number variation in a familial overgrowth condition.
Am J Med Genet C Semin Med Genet
; 181(4): 644-649, 2019 12.
Article
em En
| MEDLINE
| ID: mdl-31762227
ABSTRACT
We describe an overgrowth condition associated with X-linked copy number variation. Three brothers displayed an overgrowth pattern at birth that continued postnatally. Clinical findings included macrocephaly, distinctive facial features, developmental delay and variable clubfoot. Normal fetal growth was noted until the third trimester by Hadlock standards, revealing a late gestational overgrowth pattern. Microarray analysis in the family showed a maternally inherited 680 kb copy number duplication at Xq26.1-q26.2 in all three brothers. Molecular sequencing for known overgrowth conditions including GPC3, Sotos 1 (NSD1), Malan (NFIX), Perlman (DIS3L2), Weaver (EZH2), Opitz-Kaveggia (MED12) loci were negative. BWS IC1 and IC2 methylation and CDKN1C testing was also negative. Normal IGF1 levels excluded X-linked acrogiantism. The duplicated region Xq26.1-q26.2 contained IGSF1 and at least part of the lncRNA FIRRE. IGSF1, a highly expressed pituitary immunoglobulin superfamily gene, was recently implicated in a genome-wide association study of canine size. IGSF1 variants were associated with large canine breeds compared to smaller breeds. Our findings support the hypothesis that an X-linked variant encompassing the IGSF1 region may be associated with body size. Although IGSF1 loss has been noted in human hypothyroidism, this is the first reported phenotype in a family with copy number duplication in the region. Our findings suggest that prenatal evaluation, cross-species evaluation, Mendelian, and GWAS studies may describe a distinctive familial condition and its corresponding phenotypic features.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Variações do Número de Cópias de DNA
/
Transtornos do Crescimento
Tipo de estudo:
Guideline
Limite:
Child, preschool
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Humans
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Male
Idioma:
En
Ano de publicação:
2019
Tipo de documento:
Article