A multilocus genotype is the combination of alleles found at two or more loci in a single individual.
For example, in a diploid species, if there are two SNP loci and the first locus has alleles A and G, while the second locus has alleles T and C, the multilocus genotype can be represented as {A/G,T/C}. If the genome is not haploid then the multilocus genotype does not necessarily determine which alleles co-occur on chromosomes. In the example, if the two loci are located on the same chromosome the possibilities are either {A-T,G-C} or {A-C,G-T}. Where A-T represents a haplotype with alleles A and T together on one chromosome and G and C together on the other. If the haplotypes are determined the multilocus genotype is referred to as a phased genotype, otherwise it is referred to as unphased. Some authors[1][2] suggest that the term multilocus genotype should only be applied to phased multilocus data while others[3] apply it to unphased multilocus data as well. The combination of alleles at two or more loci on a single chromosome make up a haplotype and the two haplotypes in a diploid individual make up the diplotype (a synonym for a phased multilocus genotype).
References
edit- ^ Thompson, Elizabeth A. (2000). "Statistical Inference from Genetic Data on Pedigrees". NSF-CBMS Regional Conference Series in Probability and Statistics. 6. doi:10.1214/cbms/1462106037. ISBN 0-94-0600-49-8. JSTOR 4153187.
- ^ Lange, Kenneth (2003). Mathematical and Statistical Methods for Genetic Analysis. New York: Springer-Verlag. p. 4. ISBN 0-387-95389-2.
- ^ Pritchard, Jonathan K.; Stephens, Matthew; Donnelly, Peter (2000). "Inference of population structure using multilocus genotype data". Genetics. 155 (2): 945–959. doi:10.1093/genetics/155.2.945. PMC 1461096. PMID 10835412.