Background and objectives: Cow's milk allergy (CMA) is the most common food allergy in young children. Previous studies have reported that single-nucleotide polymorphisms (SNPs) are associated with CMA. The extent to which SNPs contribute to the occurrence of CMA is unknown. The purpose of this study was to investigate the independent relevance of genetic predisposition to CMA in Chinese children.
Methods and study design: 200 infants with CMA and 799 healthy controls aged 0-12 months were included. Five previously identified genetic variants (rs17616434, rs2069772, rs1800896, rs855791 and rs20541) were genotyped. Logistic regression was used to analyze the genetic associations or their interactions with a family history of allergy on CMA.
Results: Among the five SNPs, only IL10 rs1800896 was significantly associated with CMA (odds ratio (OR) 1.60, p=0.042). Each 1-risk allele increase in the genetic risk score (GRS) was suggestively associated with an 11% higher risk of CMA (1.11: 0.99-1.27, p=0.069) and a 45% increased risk of CMA in the GRS high-risk group compared to the GRS low-risk group (1.45: 1.02-2.06, p=0.037). Furthermore, parental allergy also increased the risk of CMA among children (1.87: 1.46-2.39, p<0.001). Importantly, parental allergy exacerbated the genetic effect on the risk of CMA.
Conclusions: The rs1800896 variant in the IL-10 gene is associated with CMA in Chinese children. In addition, the GRS had an interaction with parental history of allergy, implying that genetic risk for CMA was exacerbated among those with parental history of allergy.