The abbreviation for single-nucleotide polymorphisms studied after the HGP is SNP.
A single-nucleotide polymorphism is a variation at one DNA base position among individuals or chromosomes. For example, one person may carry an A at a location where another carries a G. Most SNPs do not cause disease, but some can influence traits, drug response, or susceptibility to particular conditions.
After the HGP’s main sequencing phase, the International HapMap Project examined how SNPs are organized into inherited patterns called haplotypes. HapMap used samples from populations including Yoruba people in Nigeria, Japanese people in Tokyo, Han Chinese in Beijing, and people of European ancestry. These data helped researchers track genetic variation and perform genome-wide association studies.
SNP is often confused with RFLP, STR, or CNV. RFLPs are variation patterns detected through restriction fragments, STRs involve short repeated sequences, and CNVs involve gains or losses of larger DNA segments. SNP is the precise abbreviation for a one-base variant.