Linkages and associations between the @entity13156 ( @entity13156 ) gene and XXXX body composition in the Qu  bec Family Study.

@entity1 @entity13156 @entity28 @entity13159 @entity13161 @entity13157 @entity1386
OBJECTIVE: To investigate linkage and association between the @entity13156 ( @entity13156 ) gene and body composition variables in the Quebec Family Study (QFS). DESIGN: Single-point linkage analysis using families, and covariance and chi-square analyses using normal weight and @entity28 unrelated subjects from QFS. SUBJECTS: 169 nuclear families were used for linkage study. 308 unrelated subjects (146 males; 162 females) from these families were used for chi-square testing of genotype and allele distributions between subjects with body mass index (BMI) < 27 kg/m2 (n = 167) and those with BMI > or = 27 kg/m2 (n = 141), and for a series of covariance analyses using age, plus height for fat mass (FM) and @entity1386 ( @entity1386 ), as covariates. A corrected P value (P*) for multiple tests has been calculated according to P* = 1-(1-P)(number of phenotypes). MEASUREMENTS: Variables were BMI (in kg/m2), sum of six skinfolds (SF6 in mm), FM (in kg), percent body fat (%FAT) and @entity1386 (in kg). Polymerase chain react restricted fragment length polymorphisms PCR-RFLP) was used to identified a @entity13157 substitution in exon 4, a @entity13159 in exon 6, a @entity13161 in exon 14 and an automatic DNA sequencer for a CA microsatellite repeat in intron 3, and heteroduplex pattern on non-denaturing gel for a CTTT repeat in intron 16. RESULTS: Good evidence of linkage was observed for @entity13159 with FM (P = 0.005; P* = 0.02), and for the CTTT repeat with @entity1386 (P = 0.007; P* = 0.03). Weaker linkages (0.02 < or = P < or = 0.05) were also observed between @entity13159 and BMI, SF6 and @entity1386 , between the CA repeat and BMI, SF6 and FM, and between the CTTT repeat and FM. Moreover, @entity1386 values were found to be different among genotypes for the CTTT repeat polymorphism with heavier females, carriers of the 123* allele at the CTTT repeat, showing 4 kg less of @entity1386 (43.6 +/- 1.0, n = 21 vs 47.7 +/- 0.8, n = 30; P = 0.005; P* = 0.02) than non-carriers. Also, at the @entity13159 polymorphism, in lower BMI males, carriers of the Q223 allele were 4 kg lighter in @entity1386 (53.4 +/- 0.6, n = 47 vs 56.6 +/- 0.9, n = 18; P = 0.005; P* = 0.02) than non-carriers. No significant differences were observed between lower and higher BMI subjects in genotype and allele frequency distributions for any of the polymorphisms. CONCLUSIONS: These results indicate that the @entity13156 gene is involved in the regulation of the body composition in @entity1 particularly of @entity1386 in the QFS.
