X Chromosome K9

X Chromosome K9 is a modern, global admixture calculator that analyzes genetic variation specifically on the X chromosome to reveal patterns of ancestry that are shaped by sex-biased inheritance. Using a comparative model built from 33 reference populations across Africa, Asia and Europe — including detailed groups such as Yoruba, Luhya, Juhoan, Han, Japanese, Yakut, Dai, Punjabi, Bengali, Tuscan, Iberian, British and Finnish — this tool provides a complementary perspective to autosomal tests by highlighting ancestry signals that travel on the X chromosome. Who it’s for: genealogists, adoptees, family historians, population geneticists, and curious individuals seeking finer-grained insight into maternal and sex-biased ancestry. Because males inherit a single X chromosome from their mother and females inherit X chromosomes from both parents with sex-specific recombination dynamics, X Chromosome K9 is particularly well suited to detecting female-mediated gene flow, recent maternal contributions, and patterns of historical admixture that autosomal summaries can dilute. What you gain: a proportional breakdown of X-chromosomal ancestry across 33 regional and population reference groups, visual context for likely ancestral sources, and interpretive guidance on sex-biased admixture — for example, identifying African, East Asian, South Asian or European components that are overrepresented on the X relative to autosomes. Results can help trace recent maternal lines, infer historical demographic events (such as migrations, founder effects, or asymmetric mating patterns), and refine hypotheses for genealogical research. Why valuable: the X chromosome carries a unique record of population history. By focusing on X-linked variation, X Chromosome K9 uncovers signals of ancestry that can be masked in whole-genome analyses, offering an important dimension for reconstructing family and population histories. For balanced interpretation, results are best used alongside autosomal, m