Vitamin D-Gene Interaction Tied to Food Sensitization
Increased risk of food sensitization in children with CC/CT genotype in IL4 polymorphism
FRIDAY, Oct. 14 (HealthDay News) -- Vitamin D deficiency (VDD) increases the risk of food sensitization (FS) in children carrying specific genotypes, according to a study published in the November issue of Allergy.
Xin Liu, M.D., Ph.D., from Northwestern University in Chicago, and colleagues prospectively investigated the association of cord blood VDD (serum 25 hydroxyvitamin D [25(OH)D], <11 ng/ml) and FS, and whether the association is influenced by genetic variants. A total of 649 children enrolled at birth and followed-up at the Boston Medical Center were genotyped for functional single nucleotide polymorphisms (SNPs) in 11 genes involved in regulating immunoglobulin E and 25(OH)D concentrations. The effect of VDD on FS individually or in combination with the SNPs was determined using logistic regression.
The investigators found that 44 percent of the children had VDD and 37 percent had FS. VDD did not correlate with FS when examined alone, but when examined in conjunction with SNPs there was a significant interaction between IL4 gene polymorphism (rs2243250) and VDD. Children carrying CC/CT genotypes had an increased risk of FS with VDD (odds ratio, 1.79). Similar, weaker interactions were seen for SNPs in MS4A2, FCER1G, and CYP24A1. Considering all four SNPs simultaneously, there was a significant gene-VDD interaction.
"We found that low cord blood vitamin D levels significantly increased the risk of FS among children carrying certain genotypes in a prospective urban U.S. birth cohort," the authors write.