A new frequent allele is the missing link in the structural polymorphism of the human mannan-binding protein

• Main Authors: Madsen, H O, Garred, P, Kurtzhals, J A, Lamm, L U, Ryder, L P, Thiel, S, Svejgaard, A
• Format: Article in Journal/Newspaper
• Language: English
• Published: 1994
• Subjects: African Continental Ancestry Group; Alleles; Asian Continental Ancestry Group; Base Sequence; Carrier Proteins; Collectins; Denmark; European Continental Ancestry Group; Gene Frequency; Genotype; Greenland; Humans; Inuits; Kenya; Molecular Sequence Data; Polymorphism; Genetic; Sequence Homology; Nucleic Acid; eskimo*; inuits
• Online Access: https://pure.au.dk/portal/da/publications/a-new-frequent-allele-is-the-missing-link-in-the-structural-polymorphism-of-the-human-mannanbinding-protein(35cef804-e97b-448c-adeb-35126d5cec95).html

Human mannan-binding protein (MBP) is a serum lectin participating in the innate immune defence. Low MBP concentrations are explained by the dominant action of a point mutation at codon 54 of the MBP gene in Eskimos, partially in Caucasians, but not in Africans. A previously described point mutation at codon 57 was very frequent (0.23) in East Africans, low in Caucasians (0.02), and absent in Eskimos. The African population only conformed to Hardy-Weinberg expectation when assuming the existence of an unknown allele, which was subsequently found as a point mutation at codon 52. This allele appeared with a relatively high frequency (0.05) in both Africans and Caucasians, but was absent in Eskimos. Hardy-Weinberg equilibrium is now seen in the investigated ethnic groups. All cases of MBP deficiency may be explained by these three variants.