Last week I explained a little about mitochondrial DNA. So this week I thought I would do something similar for yDNA. 
A very simplistic explanation as I understand it follows. Humans have 22 pairs of autosomes and one pair of sex chromosomes (the ‘x’ and the ‘y’ chromosomes). A female receives an ‘x’ from her mother and an intact ‘x’from her father. The y chromosome determines the sex. If you receive a y chromosome you are a male if you don’t then you are a female. Males receive an ‘x’ from their mother intact and a ‘y’ chromosome intact  from their father. Therefore only a male has the y-chromosome and it comes from his fathers, fathers, fathers, fathers, back to our genetic ‘Adam’. Along the way from the genetic “Adam” mutations in the y chromosomes have occurred. Approximately 4,500 to 10,000 years ago a mutation occurred at M269. Also known as R1b1a1a2, R-M269 is the Haplogroup that is found at a higher frequency in Wales, the Basque region of Spain, Ireland,  and Western Europe, decreasing in frequency as we move east across Europe.

Here is My Paternal Line

My maiden name is Putnam and my brother is the last in a long line of recipients of the family name and  y-chromosome. Our y-DNA Haplogroup is R-M269 which is the same as my Dougherty cousins, though they are not related through their y DNA in at least the last 250 years.  My brother has no male siblings, my father had only a sister, my fathers father, only brother had a different father. The next recipient of our line of y dna went to my great grandfather’s brothers, William and Edwin both of whom had male children. 

Joseph Putnam’s Male descendants

The magenta tick marks are for female descendents. This graph shows what I know so far. Unless there is a male heir, somewhere here, I know nothing about, that does it for this line. Joseph Putnam our original pioneer to California was an only child. When I originally wrote his story we had him connected to his grandfather Timothy Putnam (1760-1835) and Sarah (Hewitt) of Charlestown N.H., when in actuality he was the son of Timothy and Betsy Dickey (Hall) of Ludlow Vermont, Timothy and Sarah’s son. Betsy died in 1833 when Joseph was almost 10 years old. His father died the following year, he was sent to live with his grandfather who died in 1835. Read more of his story here .

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