Many readings throughout the course referred to complex methods used to identify and characterize genes. This wikia page will provide background information on haplotypes and how they have been used to improve the body of knowledge of genetics.
A haplotype is a combination of single nucleotide polymorphisms, also known as SNP's, which are differences in the DNA sequence (Making SNPs Make Sense). Haplotypes are closely linked genetic markers, found on one chromosome and are inherited together (Experiential Learning Center).
SNP's occur as a result of replication errors and damage in DNA. It is a single base change in a DNA sequence that occurs in more than 1% of a population. They only occur once in human evolution (Experiential Learning Center)!
SNP's can be conserved across a genome in patterns called haplotype blocks. A set of SNP's make up a haplotype (Experiental Learning Center).
There are between 200,000 and 300,000 haplotypes in the human genome (Experiential Learning Center).
Haplotype methods are used for a number of genetic tests, however one example of their use includes mapping disease genes. By creating a haplotype map of the human genome, scientists believe they can develop comprehensive studies of human diseases (Gabriel et al., 2002).
Thanks to modern technology, there are now several computer programs which allow scientists to store haplotype maps and analyze data. One such program is called Haploview, which generates statistics and haplotype patterns from genotype data in easy-to-view and interactive ways (Barrett, Fry, Maller & Daly, 2005).
Barrett, J.C., Fry, B., Maller, J., Daly, M.J., Haploview: analysis and visualization of LD and haplotype maps Bioinformatics (2005) 21 (2): 263-265 first published online August 5, 2004 doi:10.1093/bioinformatics/bth457
Gabriel, S. B., Schaffner, S. F., Nguyen, H., Moore, J. M., Roy, J., Blumenstiel, B., … Altshuler, D. (2002). The Structure of Haplotype Blocks in the Human Genome. Science, 296(5576), 2225–2229. doi:10.1126/science.1069424
Making SNPs Make Sense. (n.d.). Retrieved November 20, 2013, from http://learn.genetics.utah.edu/content/health/pharma/snips/