ABSTRACT
BACKGROUND: Visfatin is an adipokine, associated with obesity and possibly glucose regulation. OBJECTIVE: The aim of this study was to examine the association of visfatin and its genetic variants with adiposity, cardiometabolic risk factors and obesity-related morbidities in obese children. METHODS: Anthropometric measurements, dual energy X-ray absorptiometry scan, fasting blood samples and oral glucose tolerance tests were performed for 243 obese children. We screened the visfatin gene of 24 obese subjects and then performed genotyping of identified genetic variants in other 219 obese children through direct DNA sequencing. RESULTS: Fasting serum visfatin correlated with measures of obesity and liver enzymes and was elevated in obese children with abnormal glucose tolerance and non-alcoholic fatty liver disease. The two upstream single nucleotide polymorphisms, -3187G>A (rs11977021) and -1537C>T (rs61330082), were at complete linkage disequilibrium. The AA genotype of -3187G>A was associated with higher serum visfatin (6.17 ± 0.76 ng mL(-1) vs. 3.92 ± 0.44 ng mL(-1)) and higher triglyceride (1.39 ± 0.08 mmol L(-1) vs. 1.19 ± 0.07 mmol L(-1)) as compared with the GG genotype. There was also a significant linear increase in serum visfatin across GG to GA to AA genotype of -3187G>A, indicating possible additive effect of A allele. The dominant GA + AA genotype model of +21426G>A (rs2302559) was associated with lower serum visfatin (3.83 ± 0.56 ng mL(-1) vs. 5.13 ± 0.34 ng mL(-1)) and lower plasma glucose (4.37 ± 0.08 mmol L(-1) vs. 4.77 ± 0.12 mmol L(-1)) as compared with the GG genotype. CONCLUSION: Visfatin and its genetic variants were associated with adiposity, obesity-related morbidities and adverse cardiometabolic parameters. This supported our hypothesis that visfatin plays a significant role in the development of obesity-related morbidities and cardiometabolic risk.
Subject(s)
Cytokines/genetics , Diabetic Angiopathies/etiology , Nicotinamide Phosphoribosyltransferase/genetics , Non-alcoholic Fatty Liver Disease/etiology , Obesity, Morbid/complications , Obesity, Morbid/genetics , Polymorphism, Single Nucleotide , Absorptiometry, Photon , Blood Glucose/metabolism , Body Mass Index , Cardiovascular Diseases/etiology , Child , Cytokines/blood , Diabetic Angiopathies/genetics , Diabetic Angiopathies/physiopathology , Female , Genetic Variation , Genotype , Glucose Tolerance Test , Humans , Linkage Disequilibrium , Male , Nicotinamide Phosphoribosyltransferase/blood , Non-alcoholic Fatty Liver Disease/genetics , Non-alcoholic Fatty Liver Disease/physiopathology , Obesity, Morbid/physiopathology , Risk Assessment , Risk Factors , Sequence Analysis, DNAABSTRACT
BACKGROUND: Congenital adrenal hyperplasia arising from 21-hydroxylase deficiency is associated with mutations in the CYP21 gene on chromosome 6p. This is the first report on the mutational spectrum of the CYP21 gene in Singapore. METHODS: To catalogue the mutations, ten exons of the CYP21 gene from 28 Singaporean patients were analyzed by PCR amplification and direct sequencing. RESULTS: Common mutations in descending order were the intron 2 splice site mutation (32.7% of the alleles), the I172N mutation (23.1% of the alleles), and the R356W mutation (19.2% of the alleles). Two potentially novel mutations were discovered: (1) duplication of 111 bp from codon 21 to codon 57 (exon 1) and (2) missense mutation (L261P, exon 7). There was generally a good genotype-phenotype correlation, allowing accurate prediction of the disease severity.
Subject(s)
Adrenal Hyperplasia, Congenital/enzymology , Adrenal Hyperplasia, Congenital/genetics , Mutation/genetics , Steroid 21-Hydroxylase/genetics , Adrenal Hyperplasia, Congenital/epidemiology , Amino Acid Sequence , Base Sequence , Child , Child, Preschool , DNA Mutational Analysis , Female , Genotype , Humans , Infant , Infant, Newborn , Male , Molecular Sequence Data , Phenotype , Singapore/epidemiologyABSTRACT
We report the phenotype and genotype of an Indonesian Chinese boy with type II Gaucher disease. He had a unique presentation of recurrent cyanosis from laryngospasm. He was compound heterozygous for L444P/L444P + A456P + V460V. There have been few reports of this heterozygosity and its phenoptype. This genotype-phenotype correlation will be important for physicians in genetic counselling. Type II Gaucher disease in Southeast Asia may not be as rare as was perceived, but may be a condition that is under-reported. The success of our technique together with the results have made it possible for us to perform prenatal diagnosis and carrier detection for the family.
