Noor Rain A1, Holder AA2, Ogun S2, Snounou G3, Sajiri S1, Lokman Hakim S4, Normaznah Y1
1. Biotechnology Center, Institute for Medical Research, Jalan Pahang, 50588, Kuala Lumpur. Malaysia
2. Parasitology Division, National Institute for Medical Research, The Ridgeway, Mill Hill London, NW7 1AA, UK
3. Department of Infection and Tropical Medicine, Imperial College School of Medicine, Northwick Park Hospital, Middlesex, UK
4. Parasitology Division, Institute for Medical Research, Jalan Pahang, 50588, Kuala Lumpur, Malaysia
Correspondence: Dr Noor Rain A; e-mail:
CITATION: Noor Rain A, Holder AA, Ogun S, Snounou G, Sajiri S, Lokman Hakim S, et al. Allelic variants of the Plasmodium falciparum merozoite surface protein- I gene (block 2) in Malaysian isolates. International Medical Research Journal. 1999;3(1):21–4.
ABSTRACT
Allelic variation of the Plasmodium falciparum MSP-1 gene in Malaysian isolates was studied using a nested-PCR technique directed to block 2, one of the variable regions of the MSP-1 gene. Allele-specific primers were used for the three types of block 2: Kl, MAD20, and RO33. The sizes of the amplification products were in the range of 150 to 200 bp. All three allelic types are present in Malaysian isolates. They exist either on their own or in combination with other allelic types in multiple infections. The more predominant allelic types are Kl and MAD20. Sixty three percent of the in vitro cultured P. falciparum isolates and 46% of the successfully typed isolates from Ranau, Sabah showed co-existence of parasites of both Kl and MAD20 type. The RO33 allelic type was also present in both in vitro cultured isolates and field specimens from Ranau, Sabah.
KEYWORDS: Plasmodium falciparum, MSP-1 gene, Allelic variation, Malaysian isolates