Common variant within the FTO gene, rs9939609, obesity and type 2 diabetes in population of Karachi, Pakistan

Asher Fawwad; Iftikhar Ahmed Siddiqui; Abdul Basit; Nimra Fatima Zeeshan; Syed Muhammad Shahid; Syeda Nuzhat Nawab; Sidra Siddiqui

doi:10.1016/j.dsx.2015.02.001

Common variant within the FTO gene, rs9939609, obesity and type 2 diabetes in population of Karachi, Pakistan

Diabetes Metab Syndr. 2016 Jan-Mar;10(1):43-7. doi: 10.1016/j.dsx.2015.02.001. Epub 2015 Feb 24.

Authors

Asher Fawwad¹, Iftikhar Ahmed Siddiqui², Abdul Basit³, Nimra Fatima Zeeshan⁴, Syed Muhammad Shahid⁵, Syeda Nuzhat Nawab⁵, Sidra Siddiqui⁴

Affiliations

¹ Research Department, Baqai Institute of Diabetology and Endocrinology, Baqai Medical University, Plot No. 1-2, II-B, Nazimabad No. 2, Karachi 74600, Pakistan; Department of Biochemistry, Baqai Medical University, 51, Deh Tor, Gadap Road, Near Toll Plaza, Super Highway, P.O. Box No 2407, Karachi 74600, Pakistan. Electronic address: research@bideonline.com.
² Department of Biochemistry, Baqai Medical University, 51, Deh Tor, Gadap Road, Near Toll Plaza, Super Highway, P.O. Box No 2407, Karachi 74600, Pakistan.
³ Department of Medicine, Baqai Institute of Diabetology and Endocrinology, Baqai Medical University, Plot No. 1-2, II-B, Nazimabad No. 2, Karachi 74600, Pakistan.
⁴ Research Department, Baqai Institute of Diabetology and Endocrinology, Baqai Medical University, Plot No. 1-2, II-B, Nazimabad No. 2, Karachi 74600, Pakistan.
⁵ The Karachi Institute of Biotechnology & Genetic Engineering (KIBGE), University of Karachi, Karachi 75270, Pakistan.

PMID: 25757373
DOI: 10.1016/j.dsx.2015.02.001

Abstract

Aim: To determine the effect of genetic variants within the FTO gene (rs9939609) on obesity related traits and type 2 diabetes in South Asian population of Karachi, Pakistan.

Methods: A case-control study was conducted at Baqai Institute of Diabetology and Endocrinology (BIDE), Baqai Medical University situated in Karachi. A total of 296 patients with known type 2 diabetes and 198 controls aged greater than and equal to 45 years were recruited. The Anthropometric, clinical and biochemical data was collected on a structured questionnaire. Single nucleotide polymorphism (SNP) in FTO gene was identified by Amplification Refractory Mutation System-Polymerase Chain Reaction (ARMS-PCR). Association between the single nucleotide polymorphism and categorical variables such as type 2 diabetes and obesity category was tested through logistic regression analysis.

Results: We observed a strong association of the minor allele A at rs9939609 with type 2 diabetes. Significant difference was observed in frequency of FTO genotype when diabetic subjects were compared with controls in co dominant, dominant and recessive models. This association remained significant even after adjusting for body mass index (BMI) and for waist circumference. The frequency of homozygous risk Alleles (AA) was found to be higher in obese & overweight (≥ 23 kg/m(2)) and females with central obesity in our study population. The association of FTO variant with BMI and central obesity does not reach to statistical significance.

Conclusion: In the study population of South Asian ancestry, variants of the FTO gene predispose to type 2 diabetes, but not entirely through their effect on BMI.

Keywords: FTO; Karachi; Obesity; Pakistan; Type 2 diabetes.

MeSH terms

Adult
Alpha-Ketoglutarate-Dependent Dioxygenase FTO / genetics*
Asian People / genetics
Body Mass Index
Case-Control Studies
Diabetes Mellitus, Type 2 / genetics*
Genotype
Humans
Middle Aged
Obesity / genetics*
Pakistan
Polymorphism, Single Nucleotide*

Substances

Alpha-Ketoglutarate-Dependent Dioxygenase FTO
FTO protein, human