Archive for July, 2013

DNA / Genealogical Comparison Guidance

Can you suggest texts that explain how to read chromosome segments so as to determine family tree branches?  A utility or  app into which to plug selected chromosome data and generate probabilities would be ideal. GEDmatch does not currently provide the triangulation utility which did help locate and populate potential branches which could then be matched against known family trees.

Thousands of cousins have  turned up via various genetic testing services.  The labs propose generational distance.

Certain individuals share the same chromosome fragment(s).   Clearly segments over 6 cMs strongly indicate cousinage probability and the larger the segments the stronger the probability.  One can then infer that, the more segments shared, the stronger the cousinage probability.  But how does one read those segments to get the most out of the analysis?

GEDmatch provides  several Admixture analysis utilities which shows you the regional DNA sharing for each segment of  each chromosome.  What is the value in this if one can then determine that shared segments contain specific regional contributions, e.g. north-east Europe, West Asia etc?

There are likely to be other bits of wisdom the appropriate books or utilities could provide.

Where are they?

Thanks.

Ian

 

 

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