37 & 67 Marker test performed by Family Tree DNA

10/8/2021 y-dna results

 *DNA that is carried on the Y chromosome can only be passed from father to son.  This is why, even though R. W. Frey and W. N. Cossitt have the same Great Great Grandfather (Timothy Hopkins Cossitt 1817-1884), they are not a perfect match.  The Y-DNA for R. W. Frey came from Heinrich Frey who was born in Germany in 1673.  The Y-DNA from the five Cossitt Cousins, E. Corsette and two Cossette Cousins named above came from Jean Cosset who was probably born in either 1634 or 1642 in Saint-Etienne des Loges, France.  When all of the Cossitt, Corsette and Cossette Y-DNA  is compared to that of R. W. Frey, there are a total of 26 out of 37 matches. This shows that males that come from European origins have many common Y-DNA Allele Values.  In the 259 tests (Cossitt Corsette, and Cossette 37 marker tests only) there are 256 exact matches.

Mutations randomly occur in nature and are shown above as a mismatch.  Look at Locus Designation CDY for the mismatch between J. N. Cossitt and the others.  This mutation occurred from the line of Rene Cossitt Jr. to his son Ambrose, but it is impossible to tell at which generation or with whom this mutation occurred without testing all of the living Cossitt males that descended from Ambrose Cossitt Sr.

In our case, genealogy research has shown that the Most Recent Common Ancestor for J. N. Cossitt, C. D. Cossitt and W. N. Cossitt is Rene Cossitt Sr., the father of Rene Jr., François, and Timothy.  This is a total of 7 generations for J. N. and W. N.  Cossitt and 8 generations for C. D. Cossitt.  The MRCA for J. N. Cossitt , H. D. Cossitt , and R. L. Cossitt is  Rene, Jr, the father of Ambrose, Silas and Asa.  (All at 6 generations.) The MRCA for all of the above tested males is Jean Cosset which is one additional generation.

The Y-DNA carried by the above named Cossitt Cousins is extremely homogeneous when compared to the general male population with European origins.  While all eight of these Cossitt (Corsette and Cossette) surnamed individuals have identical Allele for the first 12 Locus designations, there are over 1000 other tested males (without the surname of Cossitt) that also have these same 12 Allele with more being reported every month.  When the first 25 Allele for our Cossitt (Cossette) males are compared to other tested random males, there are 42 without the Cossitt (Corsette and Cossette) surname who have only one mismatch and many more with only two mismatches.  When the 37 marker test is compared, there are no other exact matches found.  J. N. Cossitt and the other tested Cossitt (Cossette) males have 1 mismatch (E. Corsette had 2 mismatches) and the next closest at this time are 4 males with four mismatches.  It is for this reason that any other Cossitt male desiring to be tested must have all 37 markers tested. 

Family Tree DNA estimates that when there is a 36 out of 37 Allele match, then there is a 60% chance the MRCA is within 4 generation and an 80% chance that the MRCA is within 7 generations.  If there is a complete match on all 37 Alleles they estimate that the MRCA has an 80% chance within 4 generations and a 95% chance within 6 generations. 

For more discussion on the test results of Yves Cossette and Roger Cossette see "Where was Rene born?".


Rene Cosset (1690c-1752)                          Rene Cosset (1690c-1752)                         Rene Cosset (1690c-1752)
Rene Cossitt Jr. (1722-1810)                       Francois Cossitt (1726-1816)                      Rene Cossitt Jr. (1722-1810)      
Ambrose Cossitt (1749-1809)                      Roswell Cossitt (1763-1844)                       Silas Cossitt (1758-1819)                  
Ambrose Cossitt Jr. (1785-1866)                  Jesse Cossitt (1794-1843)                          H. D. Cossitt (1801-1877)              
John Francois Cossitt (1811-1882)               Newton Cossitt (1829-1911)                        H. D. Cossitt Jr. (1859-1924)
Henry Ambrose Cossitt (1852-1928)             Leonard Randles Cossitt (1876-1930)          H. D. Cossitt III (1899-1985)                   
John Henry Cossitt (1880-1954)                   Newton Neville Cossitt (1902-1965)
                                                                      Gerald Robert Cossitt (1925-2000)

Rene Cosset (1690c-1752)                          Rene Cosset (1690c-1752)                         Rene Cosset (1690c-1752)
Timothy S. Cossitt (1731-1795)                    Rene Cossitt Jr. (1722-1810)                      Timothy S. Cossitt (1731-1795)
Timothy J. Cossitt (1754-1836)                     Asa Cossitt (1754-1838)                            Timothy J. Cossitt (1754-1836)
Calvin Cossitt (1786-1867)                           Louis Capet Cossitt (1793-1847)                 Calvin Cossitt (1786-1867)      
Timothy Hopkins Cossitt (1817-1884)           Frederick Gray Cossitt (1839-1883)             Timothy Hopkins Cossitt (1817-1884)
Arthur Cossitt (1854-1932)                           Louis Germain Cossitt (1866-1950)             Harlow Hopkins Cossitt (1860-1952)           
Lester Arthur Cossitt (1892-1934)                 Hubert Pearl Cossitt (1900-1971)                Nancy Harriet Cossitt (1887-1957)  
                                                                                                                                           Nada Mildred W  (1906-2009)