The Y Chromosome is passed down the male line father to son unaltered except for the occasional mutation. The following table gives the Short Tandem Repeats and the number of repetitions. A short tandem repeat in DNA occurs when a pattern of two or more nucleotides are repeated and the repeated sequences are directly adjacent to each other.
This means membership of Haplogroup R1b (M343). Some 60% of "English" people belong to this group which dominates in Western Europe and reaches 80% in the Celtic areas. The M343 mutation was discovered in 2004 and occured some 30,000 years ago, and identifies descendents of Cro-Magnon man.
The ealiest ancestor is M168 who lived the African Rift Valley about 50,000 years ago. M89 lived about 45,000 years ago in North Africa or the Middle East. M9 lived in Iran about 40,000 years ago in the Upper Paleoithic. M45 lived in Central Asia about 35,000 years ago. M207 was in a group moving west towards Europe about 30,000 years ago. M173 was the ancester of Modern Europeans.
| STR | Repeats |
| DYS19a | 14 |
| DYS19b | - |
| DYS385a | 11 |
| DYS385b | 14 |
| DYS388 | 12 |
| DYS389I | 13 |
| DYS389II | 29 |
| DYS390 | 24 |
| DYS391 | 10 |
| DYS392 | 13 |
| DYS393 | 13 |
| DYS426 | 12 |
| DYS437 | 15 |
| DYS438 | 12 |
| DYS439 | 12 |
| DYS441 | 14 |
| DYS442 | 17 |
| DYS444 | 12 |
| DYS445 | 12 |
| DYS446 | 13 |
| DYS447 | 25 |
| DYS448 | 18 |
| DYS449 | 29 |
| DYS452 | 30 |
| DYS454 | 11 |
| DYS455 | 11 |
| DYS456 | 16 |
| DYS458 | 20 |
| DYS459a | 9 |
| DYS459b | 10 |
| DYS460 | 11 |
| DYS461 | 11 |
| DYS462 | 11 |
| DYS463 | 25 |
| DYS464a | 15 |
| DYS464b | 15 |
| DYS464c | 17 |
| DYS464d | 17 |
| DYS464e | - |
| DYS464f | - |
| GGAAT1B07 | 10 |
| YCAIIa | 19 |
| YCAIIb | 23 |
| Y-GATA-A10 | 14 |
| DYS635 | 23 |
| Y-GATA-H4 | 12 |