Y-STR Haplotype
Definition
The combination of allele values across all Y-chromosome STR loci typed in a single analysis. Reported as a string of allele values per locus. All males in a direct paternal lineage share the same haplotype (subject to rare mutational differences).
- Composition
- Combination of allele values across all Y-STR loci typed
- Reported as
- A string of allele values per locus
- Inheritance
- Shared by all males in a direct paternal lineage
- Exception
- Rare mutational differences between relatives
Common questions
Why can a Y-STR haplotype match not identify a single suspect on its own?+
Because the haplotype is shared across an entire paternal lineage, a match only narrows the pool of possible donors to a father, brothers, paternal uncles, cousins and other male relatives in that line, so the evidence's strength depends on haplotype frequency in a reference database rather than individual uniqueness.
How do mutations affect Y-STR haplotype matching between relatives?+
A mutation at one or more loci can occur during transmission from father to son, producing a slightly different haplotype between otherwise closely related males; laboratories account for this by allowing a small number of locus mismatches when assessing a plausible shared paternal lineage.
Related terms
- Argus X-12 QS
- Investigator Argus X-12 QS (Qiagen), the most widely validated commercial X-STR multiplex kit. Amplifies 12 loci in four linkage groups; used with...
- PowerPlex Y23
- Commercial Y-STR multiplex kit (Promega Corporation) amplifying 23 loci, overlapping substantially with Yfiler Plus. The 20-locus YHRD core set is covered by...
- X-STR Linkage Group
- A cluster of X-STR loci that are physically linked on the X chromosome and transmitted as a haplotype block in females. Loci...
- Yfiler Plus
- Commercial Y-STR multiplex kit (ThermoFisher Scientific) amplifying 27 loci in a single PCR reaction. Current standard for Y-STR casework in many US,...
- YHRD
- Y-Chromosome STR Haplotype Reference Database, maintained at the Charité Berlin and freely accessible at yhrd.org. Contains over 340,000 haplotypes from 124 countries....