Does anyone here understand haplotypes and how to determine your own haplotypes? As far as I know they're different from SNPs in that they are combinations of several genes rather than just a single SNP. Here's a simple example of what I am talking about "A haplotype previously identified for association with OCD [Dickelnet al., 2006], including this SNP (rs301430–rs301979),was also significant under a recessive model. The T–G haplotype type was undertransmitted to individuals with autism." What confuses me is that it doesn't seem to discuss the existence of two alleles. Does this mean that rs301430 "TT" and that rs301979 "GG" defines this haplotype and that the AA-CC would indicate not having this haplotype? Also I am also wondering what "undertransmitted" means in this context.