Common FSNP variants of fourteen Bardet-Biedl syndrome genes and adult body mass

Authors

  • Ruth Z. Birk,

    1. Department of Nutrition, Faculty of Health Sciences, Ariel University Center, Israel
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  • Sergey Ermakov,

    1. Department of Anatomy and Anthropology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
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  • Gregory Livshits

    Corresponding author
    1. Department of Anatomy and Anthropology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
    2. Department of Twin Research and Genetic Epidemiology, King's College London, UK
    • Department of Nutrition, Faculty of Health Sciences, Ariel University Center, Israel
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  • Funding agencies: This study was supported also by grant #994/10 from Israel Science Foundation.

Correspondence: Gregory Livshits (gregl@post.tau.ac.il)

Abstract

Objective

Bardet-Biedl syndrome (BBS) is a rare monogenic multi-systemic disorder manifesting with marked obesity. Fourteen BBS genes have been identified to date and additional loci are expected. Mutations of several BBS genes were shown to affect fat cell differentiation. The purpose was to Investigate the association between common polymorphisms in all 14 genes as a group and body weight.

Design and Methods

We investigated association between tagging single nucleotide polymorphisms (tSNPs) located between 10 kb upstream and downstream from the transcribed sequences of each of 14 BBS genes, and body weight and fat in 2462 adult women from the UK Twins study. Significant results were further tested in a confirmation sample of 2003 women from the same cohort and additionally in the GIANT consortium population (n = 123,865).

Results

105 SNPs in 14 BBS genes were selected and tested in the first cohort of women for association with the body weight and fat related phenotypes, i.e. weight, body mass index (BMI), total body fat (assessed by DEXA), total fat/height2, and total fat/weight. We used principal component (PC) derived using the latter five traits as a primary phenotype for this study. Of the 105 SNPs, 3 variants in BBS9 and BBS11 showed evidence of nominally significant association with elevated body weight and fat. However, none of the associations survived multiple-testing correction.

Conclusions

The results suggest that common variation in 14 BBS genes (within or adjacent to the genes) are unlikely to have a substantial effect on body weight and fat in the European population.

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