MCT1(SLC16A1) is the first member of the monocarboxylate transporter (MCT) and its family is involved in the transportation of metabolically important monocarboxylates such as lactate, pyruvate, acetate and ketone bodies. This study identifies genetic variations in SLC16A1 in the ethnic Chinese group of the Singaporean population (n=95). The promoter, coding region and exon-intron junctions of the SLC16A1 gene encoding the MCT1 transporter were screened for genetic variation in the study population by DNA sequencing. Seven genetic variations of SLC16A1, including 4 novel ones, were found: 2 in the promoter region, 2 in the coding exons (both nonsynonymous variations), 2 in the 3' untranslated region (3'UTR) and 1 in the intron. Of the two mutations detected in the promoter region, the -363-855T>C is a novel mutation. The 1282G>A (Val(428)Ile) is a novel SNP and was found as heterozygotic in 4 subjects. The 1470T>A (Asp(490)Glu) was found to be a common polymorphism in this study. Lastly, IVS3-17A>C in intron 3 and 2258 (755)A>G in 3'UTR are novel mutations found to be common polymorphisms in the local Chinese population. To our knowledge, this is the first report of a comprehensive analysis on the MCT1 gene in any population.