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NULL425

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See 'Y Results' tab above on right. Pin positions shown in the world map displayed with the 'Y Results' table linked to above is controlled by the individual Latitude and Longitude field entries in the individual's User Preferences. If a pin on the map is in the wrong place, it is because you have placed the wrong Latitude and Longitude data into those fields in your personal account record User Preferences section. Correct this by logging into your account using your Kit Number and Password and changing your User Preferences settings. Or contact FamilyTreeDNA for assistance in determining and entering the correct Latitude and Longitude for your entry. This is what FamilyTreeDNA.com says about Nulls at DYS425 and its relationship to the advanced marker DYF371: DYF371 is usually a four copy marker like DYS464. Its alleles are located on the palindromes P1 and P5 on the Y chromosome. See Y Chromosome Palindromic Map One of the copies on P5 can carry a mutation in the flanking region from C to T. This T-type allele was discovered as an independent marker and was called DYS425. Our lab has developed a test to detect the C- and T-type alleles for all DYF371 STR alleles simultaneously. This test is called DYF371X. We can see the T-type alleles and the C-type alleles in different fluorescent colors, so we can label each allele with c or t. A normal person without a NULL at DYS425 would look like 10c-12t-13c-14c for example. You will notice that in a DYS425 NULL result you don't have a T-type allele. This is because a C-type allele has overwritten the T-type allele during the RecLOH event. Other haplotypes may have two T-type alleles that may have occurred by the reverse copying process. Consequently these persons will have two DYS425 alleles. Some persons who get a DYF371 result may notice that they have an odd number of alleles at this marker (3 or 5). This occasionally happens if a deletion or duplication occurs at the large P1 palindrome. Asymmetric markers that are located on different palindromes make such events visible while regular multi-copy markers (like DYS459, CDY, DYS464) are hard to figure out their molar equivalents of alleles in each genome. If you have a deletion or duplication on P1, don't panic! Today we know that many (almost all) persons with abnormal palindromic conformations at P1 or P2 are still perfectly fertile and can produce healthy children. Even whole haplogroups (like N) carry a deletion at P1/P2 as one of their characteristic markers on their Y chromosome. If you want to find out more about possible RecLOH events, insertions or deletions on your Y chromosome we suggest ordering the markers from the Palindromic Pack (Panel 5). Source: Presentation on Palindromic Markers at FTDNA conference 2006 by Thomas Krahn See:RecLOH at WikipediaGene Conversioni at Wikipedia Some papers with discussion of marker DYS425:Diagnostic Y-STR Markers in Haplogroup G by Phillip G. Goff and T. Whit Athey