Genetic variants in the mannose receptor gene (MRC1) are associated with asthma in two independent populations.

Mannose receptor is a member of the C-type lectin receptor family involved in pathogen molecular pattern recognition and thought to be critical in shaping host immune responses and maintaining homeostasis. The aim of this study was to investigate potential associations of genetic variants in the MRC1 gene with asthma in two independent populations. Seven single-nucleotide polymorphisms (SNPs; rs2477637, rs2253120, rs2477631, rs2477664, rs692527, rs1926736, and rs691005) in the MRC1 gene locus were genotyped and evaluated regarding association with asthma in 870 unrelated Japanese subjects (446 asthmatics, 424 controls). The same markers were validated in 176 unrelated African-American subjects (86 asthmatics, 90 controls). Suggestive evidence of association between five SNPs (rs2477637, rs2253120, rs2477664, rs692527, and rs1926736) and asthma was observed in the analysis of the Japanese population independent of sex, age, smoking status, and atopic status. SNPs rs692527 and rs691005 showed significant association with asthma in the African-American population. Haplotypes containing two linked SNPs (rs692527 and rs1926736) were significantly associated with asthma in both Japanese and African-American populations. Our results suggest that sequence variations in the MRC1 gene are associated with the development of asthma in two independent and ethnically diverse populations.