Rs34276300

Since R1b1c is very common, the first interesting discovery involved a SNP in that haplogroup, rs34276300, which was found to be ancestral in one branch of R1b1c and derived in several other branches.

According to a 23andMe discussion, this is one of the SNPs that were re-analyzed in April 2009. Customers with older data may wish to redownload. SNPs affected:
 * rs4420638
 * rs34276300
 * rs3091244
 * rs34601266
 * rs2033003
 * rs7900194
 * rs9332239
 * rs28371685
 * rs1229984
 * rs28399504.