Variant alleles of the mannose binding lectin 2 gene (MBL2) confer heterozygote advantage within Crohn's families.

摘要

To The Editor: Mannose binding lectin (MBL) is a pattern recognition molecule of the innate immune system. Single nucleotide polymorphisms (SNPs) in the proximal promoter (L/H and X/Y), the 5'UTR (P/Q) and SNPs in exon 1 at codons 52 (MBL2~*D), 54 (MBL2~*B), and 57 (MBL2~*Q account for alterations in complement activation and decreased levels of MBL [1]. Researchers have reported the contribution of variant MBL alleles to disease susceptibility in infancy [2], spontaneous abortions, miscarriages and low weight newborns [3]. Other studies contemplated that the high frequency of these alleles is promoted by selective advantages providing protection against infections [4]. To evaluate the heterozygote advantage hypothesis in Crohn's disease (CD), we analyzed individuals from 37 families. The cohort comprised 138 Caucasian individuals, among them 115 individuals were unaffected and 23 individuals had CD.