X-DNA Inheritance Charts

X-DNA INHERITANCE CHARTS

Background

See Genetic Genealogy for an introduction to DNA.

The inheritance of X-chromosome DNA follows an interesting pattern, and you can only inherit this from a defined set of your ancestors. Added to that, the inheritance pattern is different for males and females. Males only have one X-chromosome, inherited from the mother (the Y-chromosome comes from the father), so their X-DNA is purely from the maternal half of the family (but only certain branches). In contrast, females inherit one X-chromosome from the mother and the other from the father, so have X-DNA from both paternal and maternal lines (but again, not from all branches).

Blaine Bettinger (The Genetic Genealogist) has written two excellent articles, which explain and illustrate the X-DNA inheritance pattern very clearly:

Debbie Parker Wayne has since provided MS Word templates in her blog-posting X-Inheritance Charts (from Deb's Delvings) – I used these (with some slight modification so the names would fit across the page and added Ahnentafel Numbers) to create X-DNA inheritance charts for me, my father, and my mother (see below). Templates for these (in Word, RTF, and PDF formats) are available on the Downloads tab.

Ann Turner has provided a list of the Ahnentafel Numbers of Ancestors who Could Contribute an X-Chromosome Segment – don't miss the instructions that the list of ancestors for females have that individual as Ahnentafel #1, whereas the list of ancestors given for males is that the individual's mother is Ahnentafel #1. Jim Turner has summarized the percentage of ancestors who can contribute to a person's X-chromosome(s) and how it is different for males and females (download Here) and has provided 5- and 6-generation X-chromosome inheritance charts for both males and females with Ahnentafel numbers and blank spaces (for your own ancestors' names) Here.