Haplotypes, groups of closely linked alleles that tend to be inherited together, can be used to map human disease genes very accurately.
All our chromosomes come in pairs, one in each pair inherited from each parent. While each chromosome of a pair contains the same genes in the same order, the sequences are not identical. For example, there are single nucleotide polymorphisms (SNPs) approximately every 1000 nucleotides. It is therefore possible to distinguish sequence variants that come from our mother and our father. These are termed maternal and paternal alleles.
shifting paradigms 