Mannose-binding lectin polymorphisms in common variable immunodeficiency.

Common variable immunodeficiency (CVID) is a heterogeneous group of disorders, characterized by hypogammaglobulinemia and increased susceptibility to infections, autoimmunity and malignancies. This study was performed to analyze the Mannose-binding lectin (MBL) polymorphisms in Iranian patients with CVID. Thirty-five CVID patients who were treated at Children's Medical Center and 100 matched controls were enrolled in this study. Sixth single-nucleotide polymorphisms of the MBL gene were analyzed using PCR-SSP method. Comparison of MBL exon 1 coding alleles between patients and controls revealed that A allele (wild-type) was significantly decreased in CVID group, whereas B allele was overrepresented in the patient group. High frequency of heterozygous (A/O) in the patient group and high frequency of homozygous for wild-type coding regions in the control group were detected. Comparison of MBL haplotype promoters between CVID patients and controls showed that LYPB haplotype was significantly overrepresented in the CVID group. Mutant and low-producing MBL alleles and haplotypes might reflect as an associated genetic factor in CVID patients, which could play as a susceptibility factor in CVID.