Genetic Polymorphism of Human Complement Factor I (C3b Inactivator) in the Chinese Han Population

Abstract

The human complement factor I (IF) polymorphism has been analysed by polyacrylamide gel isoelectric focusing electrophoresis of neuraminidase-treated EDTA plasma samples followed by immunoblotting and enzymatic detection. In a population study among 121 random individuals from Chengdu, PR China, three different common phenotypes were observed. The results show that IF is polymorphic in the Chinese population. The allele frequencies were as follows: FI*A = 0.153, FI*B = 0.847. The distribution of observed phenotypes was in accordance with the Hardy-Weinberg equilibrium. In comparison to other Asian population studies, the frequency of the IF*A allele was the highest in the Chinese population studied here.

Molecular basis of complement factor I (CFI) polymorphism: one of two polymorphic suballeles responsible for CFI A is Japanese-specific

“…The highest frequencies were observed in Han Chinese from Changsha and the second highest in Thais. An isoelectric focusing study showed that Chengdu had the highest frequency for CFI*A (0.153) among the data obtained to date (Zhang et al 1999). This haplotype flowed into Japan and Korea with fairly high frequencies.…”

Reference Typing Report for Complement Components C6, C7 and C9 Including Mutations Leading to Deficiencies

“…In contrast to C7 IEF allele frequencies, those for C7*M (and thus C7*N) are very similar for Caucasians and Mongoloids, ranging from 0.775 to 0.82 [28,38], but different for Blacks from Ecuador and South Africa (0.88 25]. As for C6, C7 IEF allotypes are characterized by a major and several minor bands (of which the nearest one towards the anode is shown).…”