How to use DNA information to learn more about your family’s ancestry and geographical origins is the subject of tonight’s meeting of the Nevada County Genealogical Society. Beginning at 6:30 p.m. in the Community Room of the Madelyn Helling Library in Nevada City, Jim Rader will discuss the different types of available tests, what they reveal and how to interpret the results. Topics will include genetic markers on mitochondrial DNA, which is passed down each generation from mother to child, to reveal your direct maternal deep ancestry, and markers on the Y chromosome, which is passed down from father to …