X-Chromosome: The X-tra Special Chromosome

By Emily Aulicino for the Genealogical Forum of Oregon (GFO) Bulletin

What makes the X-chromosome so special? Mainly it is a pattern of inheritance. Like the other twenty-two chromosomes, it randomly recombines in meiosis, but unlike the other twenty-two, only certain ancestors are contributors. Furthermore, males and females inherit differently.

INHERITANCE

The X-chromosome is one of the two sex chromosomes, and it helps determine gender. A female receives two X-chromosomes, one from her father and one from her mother. A male has only one X-chromosome, which he receives from his mother. At conception (actually at meiosis), a mother’s two X-chromosomes go through a recombination process, thus scrambling segments on the two chromosomes and even moving some segments from one chromosome to the other. The mother gives one of the randomly recombined X-chromosomes to her child (son or daughter), but each child receives a different randomly-recombined X-chromosome. Fathers, however, have only one X-chromosome that is passed only to their daughters without going through the recombination process. Fathers do not give an X-chromosome to their sons because they give them the Y-chromosome.

However, the father’s X-chromosome is a random mix of his parents and of his ancestors who were able to contribute to this chromosome.

Due to the way the X-chromosome is passed to the next generation, the inheritance of it varies between the genders and only specific ancestors can contribute. Naturally, as females get two X-chromosomes, they receive more matches than males, and because males receive their X from their mothers, their matches will be only on their mother’s half of their pedigree chart. As it can be difficult to visualize the route of inheritance for each gender, using the appropriate list of numbers (figure 1) from an ahnentafel chart or completing the fan chart created by Dr. Blaine Bettinger (figure 2) is quite helpful. The percentages in parenthesis after the numbers in the second table (figure 1) are the estimated average amounts contributed by that ancestor for the male inheritance. Due to recombination from a mother’s X-chromosomes, actual percentages cannot be confidently provided.

With recombination, it is unlikely that a female will receive 50 percent of her X-chromosome from her moth­er’s father and 50 percent from her mother’s mother. It is more likely to be a far different percentage anywhere from 0 percent to 100 percent for either of the parents. This means any ancestor can be over or under repre­sented in the X-chromosome, according to Dr. Bettinger, the Genetic Genealogist (http://www.thegeneticgene­alogist.com/2009/01/12/more-x-chromosome-charts/). For this reason, one should not assume that finding the common ancestor for a match will be easy. However, you can more easily determine who may have contributed a segment of the X-chromosome by using the tables (See Figure 1) or by using the fan charts prepared by Dr. Blaine Bettinger (See Figure 2). Remember to use the correct one for your gender.

FEMALE INHERITANCE WITHOUT PERCENTAGES

1	15	43	62	106	125	183	219	246
2	21	45	63	107	126	186	221	247
3	22	46	85	109	127	187	222	250
5	23	47	86	110	170	189	223	251
6	26	53	87	111	171	190	234	253
7	27	54	90	117	173	191	235	254
10	29	55	91	118	174	213	237	255
11	30	58	93	119	175	214	238
13	31	59	94	122	181	215	239
14	42	61	95	123	182	218	245

                        Figure 1 from Genetic Genealogy: The Basics and Beyond, p. 43

MALE INHERITANCE WITH PERCENTAGES

1	31 (12.5%)	109 (12.5%)	213 (12.5%)	238 (3.125%)
3 (100%)	53 (25%)	110 (6.25%)	214 (6.25%)	239 (3.125%)
6 (50%)	54 (12.5%)	111 (6.25%)	215 (6.25%)	245 (6.25%)
7 (50%)	55 (12.5%)	117 (12.5%)	218 (6.25%)	246 (3.125%)
13 (50%)	58 (12.5%)	118 (6.25%)	219 (6.25%)	247 (3.125%)
14 (25%)	59 (12.5%)	119 (6.25%)	221 (6.25%)	250 3.125%)
15 (25%)	61 (12.5%)	122 (6.25%)	222 (3.125%)	251 (3.125%)
26 (25%)	62 (6.25%)	123 (6.25%)	223 (3.125%)	253 (1.5625%)
27 (25%)	63 (6.25%)	125 (6.25%)	234 (6.25%)	254 (1.5625%)
29 (25%)	106 (12.5%)	126 (3.125%)	235 (6.25%)	255 (1.5625%)
30 (12.5%)	107 (12.5%)	127 (3.125%)	237 (6.25%)

                             Figure 2 from Genetic Genealogy: The Basics and Beyond, p. 43

Figures 3 and 4 Courtesy of Blaine Bettinger, Ph.D.

FINDING COMMON ANCESTORS

Although the X-chromosome and the autosomal DNA are sequenced at the same time, only Family Tree DNA and 23andMe (of the three major testing companies) al­low you to view your X-chromosome matches directly at their website with a chromosome browser feature. With AncestryDNA, you must download your autosomal DNA results into GEDmatch.com to view the X-chromosome results.

The Family Tree DNA chromosome browser offers the option of viewing your results by name and several other categories, including X matches. This allows you to see only those matches with whom you share the X-chro­mosome. If more than one person appears with the same segment, email them to determine if everyone matches everyone else. This can help females determine if the match is on one X-chromosome versus the other. Males do not have to compare their matches with each other to determine which side of their family has the match, as they only inherit their mother’s X-chromosome.

CREATING AN X-CHROMOSOME AHNENTAFEL

Because the X-chromosome is inherited differently be­tween the genders, and because not every ancestor has the possibility of contributing to the X-chromosome, it is important to create an X-chromosome ahnentafel to help you focus on the ancestral lines to assist in finding the common ancestor.

Using your genealogy software, create an ahnentafel chart, and then delete all the numbered ancestors that do not correspond to the table for your gender. When gen­erating a list for how the X-chromosome is inherited, a male starts with his mother and a female starts with herself. Keep this ahnentafel in a document you can share with your matches. (See Figure 5.)

The following is only five generations of my ahnen­tafel chart for the X-chromosome, but I offer all I have on my ancestors to my match. Notice that the following numbers are omitted as I do not inherit information on the X-chromosome for these ancestors: 4, 8, 9, 16, 17, 18, 19, 20, 24, 25 and so on. I tend to leave the data for each ancestor who is deceased in case location could be a factor. I also retain the children of the ancestors in hopes that my match recognizes someone. If I do not know an ancestor for a particular number, I list the person as in this example:  90. UNKNOWN father of Elizabeth Pryor who m.Daniel Simpson

Figure 5: ANCESTORS OF EMILY DOOLIN

for X Chromosome Matches

GENERATION NO. 1

1. Emily Doolin

GENERATION NO. 2

2. Donald Doolin

    3. Beverly Williams

GENERATION NO. 3

5. Georgia Faye Williams, born 25 Mar 1898 in Waynesville, Pulaski Co, MO; died 03 Jan 1980 in Kansas City, Wyandotte Co, KS. She was the daughter of 10. Benjamin Franklin Williams and 11. Tina May Simpson.

6. Clyde Mills Williams, born 22 Nov 1887 in Fort Scott, Bourbon Co, KS; died 08 Aug 1957 in Fort Scott, Bourbon Co, KS. He was the son of 12. John Joseph Williams and 13. Urvilla Victoria McCoon. He married 7. Emily Helen Gilmore 09 Jun 1921 in Olathe, Johnson Co, KS.

7. Emily Helen Gilmore, born 14 Dec 1890 in Grays Harbor, Grays Harbor Co, WA; died 31 Aug 1942 in Fort Scott, Bourbon Co, KS. She was the daughter of 14. Lowry Graham Gilmore and 15. Mary Adeline Ogan.

GENERATION NO. 4

10. Benjamin Franklin Williams, born 22 May 1875 in Cooper Hill, Osage Co, MO; died 05 Nov 1952 in near Waynesville, Pulaski Co, MO. He was the son of 20. Henry Jefferson Williams and 21. Syrena Simpson. He married 11. Tina May Simpson 06 Feb 1896 in Dixon, Pulaski Co, MO.

11. Tina May Simpson, born 12 Aug 1879 in Waynesville, Pulaski Co, MO; died 13 Mar 1968 in Kansas City, Wyandotte Co, KS. She was the daughter of 22. James E. Simpson and 23. Nancy Williams.

13. Urvilla Victoria McCoon, born 09 Jun 1854 in Dane Co, WI; died 09 Sep 1890 in Fort Scott, Bourbon Co, KS. She was the daughter of 26. George Henry McCoon and 27. Laura Almeda Parker.

14. Lowry Graham Gilmore, born 14 Jun 1855 in Rochester, Monroe Co, NY; died 16 Mar 1934 in Winfield, Cowley Co, KS. He was the son of 28. Robert Grey Gilmore and 29. Helen Storrier. He married 15. Mary Adeline Ogan 06 Mar 1887 in Montrose, Henry Co, MO.

15. Mary Adeline Ogan, born 11 Aug 1866 in Bureau Co, IL; died 27 Oct 1935 in Fort Scott, Bourbon Co, KS. She was the daughter of 30. Simon Peter Ogan and 31. Emily Jane Studyvin.

GENERATION NO. 5

21. Syrena Simpson, born 06 Mar 1843 in Cooper Hill, Osage Co, MO; died 05 Jan 1919 in Bland, Gasconade Co, MO. She was the daughter of 42. James Simpson and 43. Rebecca Syrene Miller.

22. James E. Simpson, born 03 May 1849 in pos. Bates Co, MO; died 29 Mar 1924 in Helm, Pulaski Co, MO. He was the son of 44. Daniel Simpson and 45. Elizabeth Pryor. He married 23. Nancy Williams ca 1869.

23. Nancy Williams, born 1849 in IL; died Bet. 1880 - 1910 in MO.

26. George Henry McCoon, born 19 Jul 1828 in Catskill, Green Co, NY or MA; died 10 Mar 1917 in Berkeley, Alameda Co, CA. He was the son of 52. James Timothy McCoon and 53. Olive Miller. He married 27. Laura Almeda Parker 18 Feb 1853 in Albion, Dane Co, WI.

27. Laura Almeda Parker, born 1834 in NY. She was the daughter of 54. Simon Parker and 55. Lauran Unknown.

29. Helen Storrier, born 28 Apr 1812 in Dundee, County Angus, Scotland; died 22 Dec 1891 in Fredonia, Wilson Co, KS. She was the daughter of 58. David Storrier and 59. Margaret Lyall.

30. Simon Peter Ogan, born 24 Aug 1826 in Columbus, Franklin Co, OH; died 23 May 1912 in Bear Creek Twp, Henry Co, MO. He was the son of 60. Evan Ogan and 61. Susan Wical. He married 31. Emily Jane Studyvin 25 Jan 1855 in Dover, Bureau Co, IL.

31. Emily Jane Studyvin, born Apr 1836 in Dover Twp, Bureau Co, IL; died 14 Nov 1912 in Henry Co, MO. She was the daughter of 62. Madison Studyvin and 63. Frances Ellis.

To use the fan charts in Figure 3 and 4, simply photocopy the appropriate chart large enough to enter the names of your ancestors. I usually copy each fan chart on two 8 x 11 inches pages and tape them together. Having both versions (male and female) handy allows you to com­plete a sample for yourself and for a match. If you are not familiar with a fan chart, it is just a different form of a pedigree chart. The tester is number one on the chart (the center circle). Then starting on the row above the circle and to the far left, enter the parent’s name that would fit in the colored box, blue for males and pink for females. After finishing each row, go to the next row above it and to the far left again and repeat the process for your grandparents, etc. Have your X-chromosome match follow the same procedure.

For a copy of both fan charts, see: http://www. thegeneticgenealogist.com/2008/12/21/unlock­ing-the-genealogical-secrets-of-the-x-chromosome/  

http://www.thegeneticgenealogist.com/2009/01/12/ more-x-chromosome-charts/  

A variation of these charts can be seen at: http:// freepages.genealogy.rootsweb.ancestry.com/~hulse­berg/DNA/xinheritance.html  

It would seem that the process of viewing who can contribute to the X-chromosome would easily provide you with the name of your common ancestor, and in some cases it does. However, many of the matches re­ceived on the X-chromosome are not large enough to ensure success. That is, due to recombination, a great number of those matches will not share enough centi­morgans (“cMs”) to discover the common ancestor. The segments look bigger on a chromosome browser graphic than they do in the table that provides the centimorgans; therefore, view the information in the table or download it into a spreadsheet. Algorithms for the X-chromosome are not as accurate as those which determine the match­es on our other chromosomes. For these reasons focus on segments that are quite large, perhaps above 20 cMs, at least. For example, I currently have 239 matches on my X-chromosome with only three matches above 20 cMs. Smaller matches could be IBS (Identical By State¹) so work with substantial segments.

SUCCESS VS. NO SUCCESS

My cousin Rebecca and I match several places on our chromosomes as well as on two segments of the X-chro­mosome. The largest segment is 39.54 cMs. I used Dr. Bettinger’s fan chart to determine our common ancestor. Although I knew Rebecca was a cousin on my mother’s line, I did not know which ancestor provided that seg­ment of our X until we completed the charts. As you can see from the charts below, the only name which is the same for both of us is Mary. This portion of our X came from her, but no doubt this segment has some elements of several of her ancestors. We can be certain that this portion of the X did not come from Mary’s husband Lowry as Lowry could not have given his X to his son Robert, the grandfather of Rebecca.

Example of using Dr. Bettinger’s fan chart to find the common ancestor between author and her cousin.

In comparing lineages with another match who shares 24.33 cMs, our common ancestor cannot be de­termined for several possible reasons. Knowing these reasons may help you understand why finding common ancestors can be difficult.

1. She does not know some of her X-chromosome ancestors.

2. I do not know some of my X-chromosome ancestors

3. The common ancestor’s segment could be under- or over-represented.²

4. Her lines go back to Hungary (now Slovakia) and Germany, very recently, and mine do not.

5. We do not know all the siblings of our ancestors who could have inherited this portion of the X-chromosome; therefore, it may be difficult to trace the lineage to the common ancestor.

SUMMARY

It bears repeating that the X-chromosome is one of the two sex chromosomes. Females receive one X from each of their parents, but males only receive the X from their mothers. The X-chromosome recombines in meiosis as do the other twenty-two chromosome, and is inherited differently by men and women. Use either the table, or Dr. Bettinger’s fan charts, to create an X-chromosome ahnentafel chart to determine which ancestors could have contributed to your X. Focus on twenty centimor­gans or more for locating common ancestors.

ENDNOTES

1.       Identical by State (IBS) ― a half-identical region (HIR) in the DNA that is a small segment of DNA that came from a very dis­tant ancestor. The smaller the segment, the less likely it is to be cut by a crossover in passing to the next generation. This means that these small segments generally get passed along whole or not at all. There is a chance that a small segment may have been passed along whole for several generations. These small segments may be from an ancestor who lived so long ago that they are beyond genealogical records.

2.       Although a child receives an X-chromosome from his or her mother, it is unlikely that that X would represent 50 percent of their maternal grandfather and 50 percent of their maternal grandmother. It is more likely that some other random amount between 0 percent and 100 percent would be inherited as the chromosome recombines. Therefore, an ancestor is likely to be under-represented (i.e., less than 50 percent) or over-represented (i.e., more than 50 percent) in the X-chromosome. The natural distribution of “under and over” is always possible. Therefore, we could be looking at a segment that gives false information in regard to the generation in which we share the common ancestor. That is, the larger the segment, usually we deduce the closer the relationship and the smaller the segment the more distant the relationship.

Written for the GFO DNA Special Interest Group, 18 Jan 2015 and appeared in the GFO Bulletin, Volume 64, No. 3, March 2015.

GFO is the Genealogical Forum of Oregon in Portland Oregon.  See their website:  www.gfo.org

For more information about DNA, please con­sider getting Emily’s book, Genetic Genealogy: The Basics and Beyond which can be purchased online at AuthorHouse.com, Amazon.com, and Barnes and Noble in paperback or as an e-book. The book can be ordered at any bookstore.

atDNA Testing: Who can Test and How can it Help your Genealogy?

 by Emily Aulicino

Anyone can test their autosomal DNA (atDNA) and match both males and females. Autosomal DNA determines your traits. It is the reason we look like our parents and siblings, but not exactly alike, except for identical twins. Even in the case of identical twins, there are differences that can be detected with detailed DNA testing.

Autosomal DNA does not provide information on just the all-male or all-female lines. This is what Y-DNA (for males) and mitochondrial DNA (mtDNA) (for females and males) testing does. Instead, autosomal DNA tests all the chromosomes except the Y chromo­some, which only males have. Autosomal testing does include the X chromosome. Because inheritance of the X chromosome varies with gender, details on the X chromosome and how it is inherited will be covered in a future lesson, or see Dr. Blaine Bettinger’s post: http:// www.thegeneticgenealogist.com/2009/01/12/more-x-chromosome-charts/.

Autosomal DNA is received randomly from each parent during meiosis. The randomness varies with each child who is conceived. Children get approximately 50 percent of their DNA from each parent. For this reason, autosomal tests will not usually give matches further back than six generations with any mathematical cer­tainty. However, there are circumstances that can allow matches to older generations. To understand this more clearly, consider that your fourth great-grandparents (sixth generation) gave 50 percent of their DNA to their child. That child (your third great-grandparent), in turn gave 50 percent of their DNA. However, that would only be about 25 percent from that fourth great-grand­parent. Therefore, the next generation (your second great-grandparent) would receive about 12.5 percent of the DNA of that fourth great-grandparent. As you can see, in a few generations, the DNA from a specific fifth or sixth great-grandparent would be negligible, in most cases.

Approximate percentage of DNA inherited from parents and grandparents:
50%	Mother, father
25%	Grandfathers, grandmothers
12.50%	Great-grandparents
6.25%	2nd Great-grandparents
3.13%	3rd Great-grandparents
1.56%	4th Great-grandparents
0.78%	5th Great-grandparents
0.39%	6th Great-grandparents
0.20%	7th Great-grandparents
0.10%	8th Great-grandparents
0.05%	9th Great-grandparents

However, if you descend from a population group that is endogamous (featuring intermarriage within a group according to custom or law such as some religious groups or some families in Colonial America), you can inherit more DNA from particular ancestors. In this situation, matches you receive can go back farther than six generations, with the testing company suggesting that the relationship of the matches is closer than they really are. Each ancestral marriage between cousins of any degree or otherwise blood-related persons increases the share of DNA they pass down from their common ancestors. The closer their relationship, the greater the effect can be. For example, one set of my paternal grand­parents were first cousins. I received a match stating a woman and I were third cousins. I already knew my connection with this woman as we had discovered our genealogical connection before DNA was ever used. She and I are really seventh cousins!

Because the atDNA from both parents mixes ran­domly at meiosis, each child typically receives different segments from each parent, so some siblings may car­ry a certain trait while other siblings do not carry that same trait. In basic biology class, we learned that some traits are recessive while others are dominant. In the diagram below, you can see a hypothetical family with four children and what they inherited based upon the DNA mixes.

Both parents have brown hair, but both have the recessive red hair gene, one parent represented in the top row, the other in the first column. The odds are they could have one child with red hair (rr), and two other children who inherited the recessive gene (Br, rB) and who could pass it along. If one of the above children who either has red hair (rr) or also carries the red hair recessive gene (Br, rB) marries a red-head or someone else with the red hair recessive gene, then there could be more red-heads in the family.

                        Father on the top line; mother on the left column

	Brown	Red
Brown	Brown Brown	Brown red
red	Brown red	red red

The companies that currently offer autosomal testing are Family Tree DNA, 23andMe, AncestryDNA, and Geno 2.0. These companies vary in some respects. Everyone but Geno 2.0 tests around 700,000 SNPs. (SNP, pronounced snip, is an acronym for single nucleotide polymorphism. In simplest terms, it is a location where the DNA changes in the general population.) Geno 2.0 is unique and deals with ancient ancestry. That company is covered separately (see companion story on page 32).

Two of the companies, FTDNA and 23andMe, offer some type of chromosome chart where you can specifi­cally see where you and your match share the same DNA. FTDNA’s Family Finder and 23andMe’s Relative Finder allow you to download the raw data files so you can re­view them in Excel or a similar spreadsheet program. AncestryDNA does not provide a chromosome chart, but you can download your raw data and view it in a third-party tool called GEDmatch. Only Family Finder allows you to see the name of the match and the per­son’s email. The other companies allow you to contact the match only through their website. As of this writing, FTDNA is allowing 23andMe(V3) and AncestryDNA users to transfer their raw data to the FTDNA database for free. https://www.familytreedna.com/Autosomal­Transfer

USING atDNA FOR GENEALOGY

Y-DNA deals only with the all-male or top line of a ge­nealogy pedigree chart (hence the surname line in most cultures), and mtDNA deals only with the all-female or bot­tom line of the pedigree chart. The atDNA gives you matches on these and the other lines of your pedigree chart, without restriction by gender, going back with some surety for about six generations from the tester. For this reason, it is wise to test as many older generations of your family as you can, as well as siblings.

Like any other DNA test, autosomal DNA tests give you matches, but it is up to you and your match to discover where on your pedigree chart your common ancestor lies. If the connection is not identified through your paper trails, atDNA information can provide an alter­native. This process involves the analysis of the data in a chart or spreadsheet. There are ways to narrow this hunt, and the basic premise is to test first to third cousins. For example, I tested my paternal first cousin Doug. If he and I match a person (I will call Mary) on the same chromosome at the same segment, then I know Mary matches on my father’s line. The next step is to deter­mine if Mary is on my father’s paternal or maternal side. To accomplish this, I tested my paternal grandmother’s nephew Dan (my first cousin, once removed). If Dan, Mary, and I match, then I know the common ances­tor is on my paternal grandmother’s line. By testing parents and child and/or several cousins, one can map one’s chromosomes and actually determine from what ancestor you received what sections or segments of your DNA. More information on chromosome mapping for those who wish to test various family members will be covered in a future Bulletin column, or get a copy of my book, Genetic Genealogy: The Basics and Beyond.

Autosomal testing is also good for adoptees who would like to contact close relatives in order to gath­er more information on their family. It is important to remember that everyone you match is related to you, however distantly.

In summation, autosomal DNA provides the tester a list of cousins with whom the tester shares a common ancestor anywhere on their six-generation pedigree chart and sometimes even farther back, as when cousins have married cousins. Mapping the chromosomes is the best way to determine the common ancestor for your matches and can be accomplished more easily by testing cousins where possible. Remember to choose the company that best fits your needs, and if possible test with all three companies to be in each of their databases in order to find more cousins.

The Genographic Project, an arm of the National Geographic Society, launched their Geno 2.0 test in the fall of 2012. This test, like Geno 1.0, is a scientific study to research the migration patterns of our ancient ancestors, but is designed to have a larger impact on population genetics informa­tion, as well as the genetic genealogy world.

Geno 2.0 does the following:

·   Tests your most ancient ancestry, so this may not be the first test you wish to do for genealogy.

·   Reports the two population groups to which the Genographic Project believes you are most related out of a total of 43 populations

·   Replaces the deep subclade (a subgroup of a haplogroup) test at FTDNA for Y-DNA, generally providing your most accurately known terminal SNP thus determining your subclade

·   Reports the percentage of your autosomal DNA that is (allegedly) originally from Neanderthal and Denisovan hominids

Geno 2.0 uses 130,000 autosomal and X-chromosomal SNPs including 30,000 SNPs from regions of interbreed­ing between extinct hominids and modern humans.

Recently, DNA evidence has shown that modern humans inbred with the Neanderthals who populated Western Eurasia. Neanderthal DNA is 99.7 percent identical to humans, and scientists believe that many humans may have inherited one to four percent of their DNA from Neanderthals. Scientists also believe some Neanderthals and some modern humans inbred with the Denisovans who populated Eastern Eurasia. It is thought that islanders in Papua New Guinea may be distant cousins of the Denisovans. With the 2008 discovery in Siberia’s Denisova cave of a 40,000 year-old finger bone of a young girl referred to as X-Woman, and a tooth of a Denisovan adult, the entire Denisovan genome has been extracted.

Besides the X-DNA and autosomal DNA, the Geno 2.0 test uses an extensive number of SNP mark­ers from mtDNA and Y-DNA that will improve the scientific knowledge of the geographic origins of our ancient ancestry by delineating between populations and narrowing the geographic areas where our ancient ancestors were located. This means breaking down a European haplogroup into smaller locations, a wonder­ful advantage for studying your ancient ancestry and its migration.

MITOCHONDRIAL DNA (mtDNA)

Geno 2.0 uses the new Phylogenetic Tree from Dr. Doron Behar’s paper, A Uniquely Anthropological Approach to Human Origins and Dispersals. Dr. Behar and his col­leagues have revolutionized the mtDNA Phylogenetic tree so that instead of comparing your mtDNA to the rCRS (Revised Cambridge Reference Sequence), the new RSRS (Reconstructed Sapiens Reference Sequence) will be implemented. The RSRS is a proposed system com­paring mitochondrial markers that include the known Neanderthal sequences. This system gives a more ac­curate view because haplogroups closer to our ancient origins will have fewer mutations than those haplogroups that are more recent, thus displaying the haplogroups in a better time-oriented sequence. In the past, the rCRS showed fewer mutations for Haplogroup H (the CRS contributor’s haplogroup) with many for haplogroups that are more ancient and closer to Mitochondrial Eve, the oldest-known female haplogroup, thus displaying mutations in a sometimes backward manner.

Y-DNA

About 15,000 SNPs with both new SNPs and SNPs from the established Y-DNA Phylogenetic Tree are included in this test. With these new SNPs, we are seeing the Phy­logenetic Tree for Y-DNA explode! There will be more Haplogroup subclades than ever before, thus helping testers determine in detail who is more closely related as well as providing younger and more geographically relevant Y-DNA branches. It not only refines the twigs (subclades) on the Y-DNA tree, it will also define the relationships between those twigs (subclades). This level of SNP testing will provide a much more accurate age for Y-SNP-based lineage to better clarify Bronze Age migrations from late Neolithic migrations, which is im­portant in understanding early history and pre-history.

This article appeared in the GFO Bulletin, Volume 64, No. 2, December 2014.

GFO is the Genealogical Forum of Oregon in Portland Oregon.  See their website:  www.gfo.org

For more information about DNA, please con­sider getting Emily’s book, Genetic Genealogy: The Basics and Beyond which can be purchased online at AuthorHouse.com, Amazon.com, and Barnes and Noble in paperback or as an e-book. The book can be ordered at any bookstore.