Genetics & Genealogy – Or why don’t I have black hair and dark skin?

Every now and then, someone asks a question that really makes you stop and think.  The question of the day is why don’t I have black hair and dark skin. For those of you who know me, this sounds like an extraordinary question. Growing up, my hair color was variable — changing from a medium brown to almost blond and back.  And my skin color is on the extreme side of light.   I moved from Seattle to Texas in the dead of winter to go to work for NASA.  My new office mates just stood and stared at me when I first showed up.  When they finally spoke to me, they said they had never seen anyone as “white” as me.  Perhaps they thought I was a ghost!

Recently as part of a genetic research project, I was asked to choose a skin tone that most closely matched my skin tone.  The chart has twenty-one skin tones on a scale from 0.0 to 10.0.
(http://ww2.gedmatch.com:8006/autosomal/skin_pigment_chart.php) The color closet to me was at 9.0.  So really far away from dark skin but not all the way to paper white either.

So maybe you are wondering how such a question would have even come up.  Which brings us back to genetics and family tree.  My maiden name is Duffy. In Gaelic, it would be spelled Ó Dubhthaigh.  Surnames are usually occupations, geographic locations, relation to someone else (son of …), or colors.  Ó Dubhthaigh is a mix of relationships and color.  Dubth is black or dark.  Various meanings attributed to Ó Dubhthaigh are: “descendant of the dark one,” son of dark, dark-skinned, black hair.  Until recently, I just considered this a curious description, since my father has red hair (still strawberry-blond at 82!) and pale skin. His sister was blond.  His older brother did have dark hair but not dark skin.

What happened recently was that I came across a Duffy/Duffey relative living in Iowa, where the Duffy’s settled after coming to America.  It turns out that the Duffy/Duffey’s that stayed in Iowa have black hair and dark skin.  So how and where did the dark coloring get “lost” in the genetic tree?

My Duffy grandparents have 6 genetically linked grandchildren.  My father only has two siblings; one a Catholic priest and a sister with one biological child. I have four siblings. All 6 of us have light-colored skin, and the darkest hair color is a medium brown.

A recent family shot!
My cousin Mary and my Dad (2014)

My grandfather was one of five children.  Two of his brothers died young, his only sister never married, and his other brother was sterile.  Both my grandfather, Francis Michael, and his brother, John James, were light-skinned when I knew them. There were no color pictures when they were young.  But they appear to have brown hair in this wedding photo.  If any of the children were dark-skinned, it would have had to have been the children who died young.

Jim & Frank Duffy at Frank’s wedding
Dr. Francis Michael Duffy

My great-grandfather was the 4th of 10 children born in America of Irish Immigrants who settled in Holbrook, Iowa. I have no pictures of my great-grandfather at all. When my great-grandfather died suddenly after an accident, his family moved first to town (Williamsburg) and later to Omaha, Nebraska, where my grandfather and his brother attended medical school.

My newly discovered relative in Iowa is a descendant of the 7th child of my great-great-grandparents. So why are the Duffy/Duffey’s who stayed in Iowa dark-skinned with black hair and our branch is pale-skinned with light hair?  I don’t know.  The field of genetics is booming with new data from the explosion of people having DNA tests for genealogical purposes.  Maybe I will find answers one day.

Both my paternal and maternal line supposedly trace back to the Three Collas, the mythical founders of the Kingdom of Airghialla in Northern Ireland, about 4 AD.

If you have had DNA testing done by Ancestry, Family Tree DNA, or 23andme, you can download your DNA results to your computer and then upload it to a free website called GEDmatch.com.  This website has some useful tools related to genetics and your DNA.