Identification of the Kna/Knb polymorphism and a method for Knops genotyping.


Journal Article

BACKGROUND: DNA mutations resulting in the McCoy and Swain-Langley polymorphisms have been identified on complement receptor 1 (CR1)-a ligand for rosetting of Plasmodium falciparum-infected RBCs. The molecular identification of the Kna/Knb polymorphism was sought to develop a genotyping method for use in the study of the Knops blood group and malaria. STUDY DESIGN AND METHODS: CR1 deletion constructs were used in inhibition studies of anti-Kna. PCR amplification of Exon 29 was followed by DNA sequencing. A PCR-RFLP was developed with NdeI, BsmI, and MfeI for the detection of Kna/Knb, McCa/McCb, and Sl1/Sl2, respectively. Knops phenotypes were determined with standard serologic techniques. RESULTS: A total of 310 Malian persons were phenotyped for Kna with 200 (64%) Kn(a+) and 110 (36%) Kn(a-). Many of the Kn(a-) exhibited the Knops-null phenotype, that is, Helgeson. The Kna/b DNA polymorphism was identified as a V1561M mutation with allele frequencies of Kna (V1561) 0.9 and Knb (M1561) 0.1. CONCLUSION: The high frequency (18%) of Knb in West African persons suggests that it is not solely a Caucasian trait. Furthermore, because of the high incidence of heterozygosity as well as amorphs, accurate Knops typing of donors of African descent is best accomplished by a combination of molecular and serologic techniques.

Full Text

Cited Authors

  • Moulds, JM; Thomas, BJ; Doumbo, O; Diallo, DA; Lyke, KE; Plowe, CV; Rowe, JA; Birmingham, DJ

Published Date

  • February 2004

Published In

Volume / Issue

  • 44 / 2

Start / End Page

  • 164 - 169

PubMed ID

  • 14962306

Pubmed Central ID

  • 14962306

International Standard Serial Number (ISSN)

  • 0041-1132

Digital Object Identifier (DOI)

  • 10.1111/j.1537-2995.2004.00615.x


  • eng

Conference Location

  • United States