SUMMARY OF SNP (September, 2012)

Classification of SNP: Near Private.

Estimated Breadth of SNP: 5 to 10 submissions.

Scope of Testing within Fingerprint: - Average - Only four tested out of fifteen possible candidates.

Dominant Surnames (positive): Brown (1), Perry (1) and Pike (1).

Year that SNPs were discovered: March, 2011.

Source of SNP: FTDNA - WTY - Perry, FTDNA ID 23996 and Y-Search KNA9C.

Baseline for SNP: Three submissions that have tested positive.
(MRCA of testing candidates based on preliminary fingerprint matches - not WTY)

Number of Positive Tests: Three known.

Number of Negative Broad Tests: 34.

Number of Negative Tests within Fingerprint (70 % match): None.

Possible Candidates (70 % match): Around four.

Pending Tests (within Fingerprint): None known.

ANALYSIS OF FINGERPRINT MARKERS

L554 is a very narrow scope Y-SNP where all but one marker in the fingerprint appears to be pre-L554 mutations. Only 487 <= 17 appear to be post L554 creation.

Marker 487 <= 17 is almost a key marker of the L554 fingerprint as it almost tracks L554. However, there is also one known negative test where 487 <= 17 is part of the Ramsey haplotype (N16295). Any submission with 487 <= 17 should be tested since so few submissions have the marker value above 50 % matches and all L554 positive have this marker value (one has tested negative).

TRENDS OF TESTING CANDIDATES

Note that the number of known testing candidates appears to be fairly typical for L21 SNPs where the number of testing candidates declines down to 70 % matches and then sees a sharp rise as non-L554 submissions dominate the under 50 % matches. However, unlike most Y-SNPs, there appears to a very good chance for fingerprint matches where both negative and positive test results should be expected. However, the transitional fingerprint matches (between 50 % and 70 % matches) have not been well tested to date, so it remains to be seen what the exact scope of this Y-SNP will be. The fingerprint for L554 is more difficult to determine than most Y-SNPs due to major genetic variation found at higher fingerprint matches. L554 appears to be one of the Y-SNPs where negative and positive test results should be expected at the same fingerprint match.

ISOGG Status - Prove relationship of L554 to other L21 SNPs

Requirements of proving L554 position on the ISOGG haplotree were met quite some time ago and L554 has been part of the haplotrees for over one year. Even with the recent discovery of L1066, all ISOGG requirements are still satisfied.

ISOGG Status - Prove genetic and surname diversity of L554

L554 satisfies both the 15 % genetic diversity requirement and the surname diversity requirement for inclusion on the ISOGG haplotree. Two submissions of L554 must have at least a genetic distance of 10 (15 % x 67 markers = 10).

DNA FINGERPRINTS

L21 Off Modal Mutations:

Markers 1 to 37: 390 >=25, 439 <= 11, 389-I >= 14, 389-II >=30 (redundant with 389-I), 437 <= 14, 449 <= 29, 464c <= 16, 460 <=10, 456 <= 15 and 442 >= 13 (10 mutations).

Markers 38 to 67: 534 >=16 and 487 >= 14 (2 mutations).

DNA Signature (L21 Project): 253-1414.

Markers 1 to 37: 389-I = 14, 437 = 14 and 456 = 15 (3 mutations).

Markers 38 to 67: 534 >=16 and 487 = 14 (2 mutations).

BOUNDARY CONDITION TESTING

Most Distant Positive Test Known (67 markers)
(from MRCA of testing candidates - not WTY):

Pike, FTDNA ID 23996, Y-Search KNA9C, 11 of 12 fingerprint match and GD = 6.

Closest Negative Test Known (67 markers)
(from MRCA of testing candidates - not WTY):

Ramsey, FTDNA ID N16295, Y-Search KU83A, 8 of 12 fingerprint match and GD = 9.