Brady Surname Project

Brady yDNA Project
  • 199 members

About us

BACKGROUND. Most persons with the Brady name trace their ancestry to Ireland.  There is really only one distinct Brady group, and the origin is placed in the Kingdom of Breifne, close to the O'Raghalllaigh (O"Reilly) sept.  The meaning and language of the name's origin is unknown.  MacBradaigh allegedly had Chieftains when first mentioned in the Annals [1]  but were more associated with several bishops and the eranaghs (church laity) of the Kilmore Diocese in the area of East Breifne which became County Cavan.  With time the name spread to local counties as well as distant ones and other countries and continents.  It is currently the 54th most commonly occurring name in Ireland.   As with all Irish septs the descendants doing yDNA genetic testing do not all match each other.  The usual reasons they do not, such as adoption, fosterage, remarriages, or marriages where the husband takes the wife's name, etc, might apply.  There were also the upheavals of rebellion, famine, migration, emigration and religious preference which might prompt one to change a last name.  For the most recent centuries adoption and/or a non paternal event remain the primary reasons for a difference in last names.   In the FTDNA Brady Surname Project about 40-50% of those with yDNA tests named Brady match within the acceptable yDNA limits of genetic distance (GD).  The Y Haplogroup is R1b-L21, and subclades Z253+, L1066+.  This group is old enough to have some with SNPs [2] that vary, so hopefully other subgroups can be identified by SNPs to compensate for the lack of genealogical documentation.   Non-matching Bradys are also primarily L21, some matching local septs or County Cavan Plantation settlers.  (Footnotes. [1] Annals of the Four Masters, covering Irish history to  AD 1616, English translation. [2] SNP,  pronounced "snip" is an abbreviation for Single-nucleotide polymorphism,  a variation at a specific position in the genome found within a population.)(1/10/2020)

Brady Project Administrators:

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