1. Identification of the gene altered in Berardinelli-Seip congenital lipodystrophy on chromosome 11q13.
- Author
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Magré J, Delépine M, Khallouf E, Gedde-Dahl T Jr, Van Maldergem L, Sobel E, Papp J, Meier M, Mégarbané A, Bachy A, Verloes A, d'Abronzo FH, Seemanova E, Assan R, Baudic N, Bourut C, Czernichow P, Huet F, Grigorescu F, de Kerdanet M, Lacombe D, Labrune P, Lanza M, Loret H, Matsuda F, Navarro J, Nivelon-Chevalier A, Polak M, Robert JJ, Tric P, Tubiana-Rufi N, Vigouroux C, Weissenbach J, Savasta S, Maassen JA, Trygstad O, Bogalho P, Freitas P, Medina JL, Bonnicci F, Joffe BI, Loyson G, Panz VR, Raal FJ, O'Rahilly S, Stephenson T, Kahn CR, Lathrop M, and Capeau J
- Subjects
- Acanthosis Nigricans complications, Chromosomes, Human, Pair 9 genetics, Cluster Analysis, DNA Mutational Analysis, Diabetes Complications, Female, Genes, Recessive, Genetic Linkage, Genetic Markers, Genetic Testing, Haplotypes, Hepatomegaly complications, Heterotrimeric GTP-Binding Proteins genetics, Humans, Hyperandrogenism complications, Hypertriglyceridemia complications, Insulin Resistance genetics, Lebanon epidemiology, Lipodystrophy complications, Lipodystrophy epidemiology, Male, Middle Aged, Molecular Sequence Data, Mutation, Norway epidemiology, Organ Specificity, Pedigree, Protein Structure, Tertiary, Proteins metabolism, Sequence Homology, Amino Acid, Chromosomes, Human, Pair 11 genetics, GTP-Binding Protein gamma Subunits, Lipodystrophy congenital, Lipodystrophy genetics, Proteins genetics
- Abstract
Congenital generalized lipodystrophy, or Berardinelli-Seip syndrome (BSCL), is a rare autosomal recessive disease characterized by a near-absence of adipose tissue from birth or early infancy and severe insulin resistance. Other clinical and biological features include acanthosis nigricans, hyperandrogenism, muscular hypertrophy, hepatomegaly, altered glucose tolerance or diabetes mellitus, and hypertriglyceridemia. A locus (BSCL1) has been mapped to 9q34 with evidence of heterogeneity. Here, we report a genome screen of nine BSCL families from two geographical clusters (in Lebanon and Norway). We identified a new disease locus, designated BSCL2, within the 2.5-Mb interval flanked by markers D11S4076 and D11S480 on chromosome 11q13. Analysis of 20 additional families of various ethnic origins led to the identification of 11 families in which the disease cosegregates with the 11q13 locus; the remaining families provide confirmation of linkage to 9q34. Sequence analysis of genes located in the 11q13 interval disclosed mutations in a gene homologous to the murine guanine nucleotide-binding protein (G protein), gamma3-linked gene (Gng3lg) in all BSCL2-linked families. BSCL2 is most highly expressed in brain and testis and encodes a protein (which we have called seipin) of unknown function. Most of the variants are null mutations and probably result in a severe disruption of the protein. These findings are of general importance for understanding the molecular mechanisms underlying regulation of body fat distribution and insulin resistance.
- Published
- 2001
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