The Null 425 yDNA Project was formed to gather data and learn more about haplogoups which have a null result for Y-STR marker DYS425. The largest null 425 by far is E-M35. The next largest are I-M223, M284 Isles, R-U106, L48, Z326, and R-L21, DF21, Clan Colla. The information about haplotypes which have a null result for marker 425 consists of test results for the DYF371X advanced marker. In 2019, Family Tree DNA stopped testing the DYF371X advanced marker.
As of May 20, 2014, there were DYF371X test results for 32 haplogroups:
A-M32, M13; 10c-10c-13c-13c
E-M35; 10c-10c-13c-13c. Variants: 10c-10c-11c-13c, 10c-10c-13c, 10c-10c-13c-13c-13c, 10c-10c-13c-14c, 10c-11c-13c-14c
I-M223, M284 Isles; 10c-10c-13c-13c. Variants: 10c-12c-12c-12c
I-M253; 10c-10c-13c-14c. Variants: 10t-11c-12t-14c
J-M92; 9c-10c-12c-13c-14c. Variants: 10c-12c-14c-14c
R-L21, DF21, Clan Colla; 10c-12c-13c-14c. Variants: 10c-12c-14c-14c
R-L21, DF21; 10c-12c-13c-14c
R-L21, DF21; 8t-10c-13c-14c
R-L21, L1065, L1335;10c-10c-13c-14c
R-L21, L193; 10c-10c-13c-14c
R-L21, M222; 10c-10c-13c-14c
R-L21, Z253; 10c-10c-13c-14c
R-L23, Z2105; 10c-10c-13c-14c
R-U106, 391=10 459a=7; 10c-10c-14c-14c
R-U106, L48, Z326; 10c-10c-13c-14c. Variants: 10c-10c-13c-13c, 10c-10c-13c-15c, 10c-10c-14c, 8c-10c-13c-14c
R-U106, L48; 10c-12c-13c-14c
R-U106, Z156; 10c-10c-13c-14c
R-U106, Z18; 10c-10c-13c-14c
Charles F. Kerchner, Jr., P.E., (Retired), a genetic genealogy pioneer, since he had a "null" at YSTR marker DYS425, launched this project with FamilyTreeDNA in March 2007 in order to learn more about Nulls at DYS425 by collecting YDNA information about those who have the null at YSTR marker DYS425. The null or 'no allele value found' event for the standard test for DYS425 seems to occur in all haplogroups but it seems to occur in some haplogroups at a higher frequency than it occurs in others. There is no universal explanation for this observation as to why it is found frequently in some groups and not in others at this point in time. Mr. Kerchner as a pioneer in this field has started various projects in the Genetic Genealogy field to collect data regarding his observations. One major project of his is the study of Observed YSTR Mutation Rates in Surname Projects.
Tibor Fehér joined this project in January 2010 as Co-Admin and eventually took over as Group Administrator from Charles Kerchner.
Peter Biggins took over as Group Administrator from Tibor Fehér in October 2013.
For helpful information and resources regarding how YDNA Genetic Genealogy works see Kerchner's DNA Info help page:http://www.kerchner.com/dna-info.htm