From ISOGG Wiki
A half-identical region (HIR) is a region of two paired chromosomes where at least one of the two alleles from one person's pair of chromosomes matches at least one of the two alleles from a different person's pair of chromosomes throughout the entire region. A half-identical region may be either identical by descent (IBD) or identical by state (IBS).
The term half-identical region was coined by the genetic genealogist Leon Kull, who developed HIR Search, a program which was set up to compare autosomal DNA test results from different testing companies.
- Half identical. A definition provided by John Robb in an article on his website entitled "DNA testing and genealogy".
- Definition of half identical region Family Tree DNA Learning Center.
- Wheaton K. Beginners' guide to genetic genealogy. Lesson 9: atDNA matches.
- An explanation of a matching half-identical segment from Don Worth