Tuesday, April 24, 2018
Understanding Our DNA Tests
Edited by Dr. Sandra Oster
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| Think of our genes (which are a unit of heredity that is transferred from a parent to offspring and is held to determine some characteristic of the offspring.) sitting on a ladder with 23 pairs of rungs called chromosomes. One slat on the rung is from your mother, the other from your father. The first rung, called #1 is the widest rung on the ladder. It has 2,968 genes. There are 890 known diseases related to this chromosome. Some of these diseases area: hearing loss, Alzheimer disease, glaucoma and breast cancer. |
All 23 rungs on the ladder which stand for the 23 chromosomes we have carry double amounts in 2 rows. One row is from our father and the other from our mother. It's pretty close to being even; 50-50. Our test from FTDNA has been identifying if a match is from either parent with a little icon of a blue male or red female or purple from both; like the child would have. Some people cannot be decided on and get no icon by their name/picture.
The genes come to us in little 1cM blocks, like a single Lego block. In genetics, a centimorgan is a measurement for distance. It is (abbreviated cM) or map unit (m.u.) is a unit for measuring genetic linkage. It is defined as the distance between chromosome positions (also termed loci or markers) for which the expected average number of intervening chromosomal crossovers in a single generation is 0.01. The thing is, they usually come to us stuck together with others, making a longer block called a segment. The longer the segment, the closer you are to the person you match with them. 1 lego block is 1cM.
The ladder is seen by the scientists as a twisted ladder, the shape of a double helix.
Notice the segments are pretty long, several on one chromosome. #1 chromosome has 4 segments.
I don't worry about the SNPs (Single Nucleotide Ploymorphisms.) They are a very slowly mutating location that is used to define haplogroups, another factor of genetics. That is important in identifying the clans your father or your mother belonged to.
The largest segment is on #9 chromosome. of 52.1cMs. Look below at chromosome #9. It's a picture of the largest segment being in this case, a long one of 52.1. It a length of 52.1 little blocks stuck together.
The smallest segment is on #21 of 7.5cMs.
A segment of 5cMs and more is counted as an important fact. Some people only get interested in the facts with a segment of 7cMs and more. . Smaller segments are not too important, possibly thought of as not as reliable scientifically.
The graph on FTDNA showing #1 chromosome match between my 1st cousin and myself: This black and yellow length is a chromosome with yellow segments on it and is the first chromosome called #1. When you are on your page in Family Tree DNA's website, you would see this and all the other 22 chromosomes. I'm showing you this one because the table below shows 4 large segments on #1 chromosome listed separately with the start and end location and how many cMs they have as well as how many SNPs that chromosome has..










| Chr | Start Location | End Location | Centimorgans (cM) | SNPs |
| 1 | 3,052,221 | 25,801,522 | 44.8 | 6,612 |
| 1 | 53,581,281 | 69,237,989 | 22.1 | 4,484 |
| 1 | 74,788,735 | 90,271,128 | 14.6 | 3,815 |
| 1 | 149,227,054 | 163,867,989 | 21.2 | 4,088 |
| 2 | 84,202,139 | 106,046,373 | 10.3 | 3,041 |
| 2 | 193,725,959 | 223,565,798 | 33.9 | 6,378 |
| 2 | 223,581,059 | 233,766,809 | 14.4 | 2,341 |
| 4 | 61,566 | 6,048,415 | 10.4 | 1,413 |
| 4 | 139,776,818 | 173,159,377 | 34.4 | 6,286 |
| 5 | 2,711,026 | 9,426,448 | 17.1 | 2,343 |
| 5 | 29,372,002 | 55,864,542 | 23.0 | 4,971 |
| 5 | 153,966,655 | 180,623,543 | 45.7 | 6,994 |
| 6 | 3,653,477 | 20,272,175 | 32.2 | 4,958 |
| 6 | 74,007,746 | 91,078,586 | 10.5 | 3,373 |
| 6 | 126,393,744 | 137,403,363 | 11.6 | 2,349 |
| 6 | 154,838,664 | 161,802,211 | 9.6 | 2,104 |
| 7 | 29,887,885 | 45,266,280 | 19.7 | 3,835 |
| 8 | 6,006,187 | 12,761,447 | 11.6 | 1,917 |
| 8 | 23,060,574 | 31,234,783 | 11.9 | 2,354 |
| 8 | 103,773,672 | 125,812,954 | 19.0 | 4,408 |
| 9 | 81,797,685 | 123,377,583 | 52.1 | 10,912 |
| 9 | 124,006,082 | 134,328,607 | 15.2 | 2,497 |
| 10 | 85,994,218 | 103,089,567 | 16.5 | 4,577 |
| 10 | 128,065,109 | 135,297,961 | 18.9 | 2,714 |
| 12 | 116,636,547 | 124,168,929 | 9.3 | 1,758 |
| 14 | 30,341,495 | 42,197,431 | 16.8 | 2,771 |
| 14 | 89,899,082 | 106,345,097 | 34.6 | 4,453 |
| 15 | 18,331,687 | 40,097,819 | 42.3 | 5,070 |
| 16 | 64,956,434 | 80,257,464 | 22.4 | 4,230 |
| 17 | 12,344 | 7,964,962 | 22.0 | 2,537 |
| 18 | 6,414,209 | 32,274,392 | 40.6 | 6,428 |
| 18 | 71,869,832 | 74,401,062 | 8.0 | 971 |
| 19 | 3,713,698 | 33,398,855 | 36.2 | 5,038 |
| 20 | 57,539,142 | 62,374,274 | 16.5 | 1,588 |
| 21 | 9,849,404 | 16,035,905 | 7.5 | 569 |
| 21 | 16,591,440 | 35,444,863 | 32.8 | 5,231 |
| 22 | 37,722,196 | 49,528,625 | 28.0 | 3,818 |
Total of segments > 7 cM = 837.6 cM
37 matching segments
Estimated number of generations to MRCA = 2.0 MOST RECENT COMMON ANCESTOR
Here's the test with the same cousin and my daughter to see what she inherited .
How did she match the #3 chromosome? I didn't have a match on #3 so how could she inherit it from me? I thought I pass genes to my daughter. How did she inherit 7.1cMs on chromosome number 3? Wouldn't they have come from her father, then?
She inherited some segments in the same piece that I passed to her, but most had lost some cMs.in the passing to her.. She gained #3's matching chromosome segment that I didn't have, I thought.
My son did not have a match with my 1st cousin on #3.
| Chr | Start Location | End Location | Centimorgans (cM) | SNPs |
| 1 | 3,025,087 | 12,086,665 | 19.3 | 2,788 |
| 1 | 74,942,731 | 90,347,366 | 14.6 | 3,835 |
| 1 | 149,581,003 | 163,732,848 | 20.9 | 3,965 |
| 2 | 82,974,238 | 106,005,245 | 10.8 | 3,251 |
| 2 | 193,071,967 | 219,949,518 | 27.9 | 5,530 |
| 3 | 36,495 | 2,749,996 | 7.1 | 1,097 |
| 4 | 139,776,818 | 173,159,377 | 34.4 | 6,299 |
| 5 | 29,249,005 | 36,391,583 | 11.1 | 1,897 |
| 5 | 153,879,500 | 172,829,402 | 29.0 | 4,943 |
| 6 | 3,362,642 | 19,807,420 | 32.4 | 4,877 |
| 6 | 126,393,744 | 137,332,306 | 11.5 | 2,347 |
| 6 | 154,838,664 | 161,802,211 | 9.6 | 2,129 |
| 8 | 23,253,923 | 31,234,783 | 11.5 | 2,309 |
| 8 | 117,536,189 | 125,770,106 | 11.4 | 2,082 |
| 10 | 85,614,149 | 99,641,440 | 13.5 | 3,854 |
| 10 | 127,998,547 | 135,297,961 | 19.1 | 2,761 |
| 14 | 89,499,502 | 106,345,097 | 35.7 | 4,560 |
| 15 | 34,667,910 | 40,092,334 | 8.1 | 1,498 |
| 16 | 64,462,524 | 80,294,248 | 23.0 | 4,475 |
| 18 | 6,414,209 | 9,689,833 | 13.6 | 1,233 |
| 18 | 71,869,832 | 74,397,540 | 8.0 | 986 |
| 21 | 9,849,404 | 16,035,905 | 7.5 | 568 |
| 21 | 16,285,114 | 26,701,936 | 19.2 | 2,892 |
Total of segments > 7 cM = 398.8 cM
23 matching segments
Estimated number of generations to MRCA = 2.6
My brother had inherited 2 large segments on chromosome #3 .They aren't the same segments that I had matched with our cousin and are big ones, too. Siblings don't always match the same segments with other people just because they are siblings.
.
| 3 | 3,391,536 | 44,079,879 | 56.6 | 11,481 |
| 3 | 129,663,879 | 193,357,386 | 74.4 | 13,730 |
Our Goldfoot Family Tree
Notice the unusual names below. They are how our ancestors were listed in the Lithuanian records. Every 10 years or so their names appeared in a different spelling of the first letter. ben means son of, which helped to identify their parents.
1 Iankel Yankel ben Abram Goldfusb: 1768 in Telsai, Telsiai, Kaunas, Lithuaniad: December 06, 1860 in Telsliai, Telsiai, Kaunas, Lithuania
..+Khana Unknownb: Abt. 1778 in Telsiai, Telsiai, Kaunas, Lithuania
.2 Abram Goldfusb: Abt. 1797 in Telsiai, Telsiai, Kaunas, Lithuania
.....3 Mendel Goldfusb: 1800
.....3 Leyba Abramov Goldfusb: 1819 in Papile, Siauliai, Kaunas, Lithuania
.........+Feyge Ioselevab: 1820
.....3 Ginda Abramovna Goldfusb: Abt. 1820 in Telsiai, Lithuaniad: January 15, 1869 in Telsiai, Lithuania
.....3 Golda Abramovna Goldfusb: 1836 in Telsiai, Lithuaniad: April 12, 1911 in Telsiai, Lithuania
.2 [3] Iosel Josel Symka ben Yankel Goldfusb: 1798 in Telsiai, Telsiai, Kaunas, Lithuania, Russiad: December 19, 1878 in Telsiai, Telsiai, Kaunas, LithuaniaOccupation: 1851 3rd guild merchant;
.....+Rashab: Abt. 1798 in Telsiai, Telsiai, Kaunas, Lithuania, Russiad: Bef. 1876 in Telsiai, Lithuania
.....3 [1] Avrohom Abraham Haim Goldfusb: Abt. 1820 in Telsiai/ Vilna, LithuaniaOccupation: Corn Merchant into Moscow
Our 3rd cousin match goes back to Iankel Yanken ben Abram Goldfus as his gggrandfather.
My 1st cousin and I go back to Iosel Josel Symka ben Yankel Goldfus as our gggrandfather. Iosel is the son of Iankel.
2 generations ago; grandfather-your father's father or your mother's father ...2 grandmothers, 2 grandfathers
3 generations ago; ggrandfather- your grandfather's father...... 4 ggrandmothers, 4 ggrandfathers
4 generations ago; gggrandfather-your ggrandfather's father 8 gggrandmothers, 8 gggrandfathers
5 generations ago; ggggrandfather: the white circle in the chart below, needed to find 4th cousins. Your gggrandfather's father. 16 ggggrandmothers and 16 ggggrandfathers
Chart to Find 4th Cousins
Our 3rd cousin, another Goldfoot, matches like this:
1. Find your circle which is black. Your father is above YOU in green. His father is above the green and is red.
2. The red circle is your grandfather. Your father's brother had a child which is also green and labeled as 1C (first cousin).
3. To find a 2nd cousin, you must go to your grandfather's father which is blue on the chart.
The child of his brother would be the first cousin of your father's brother.
1C in the white circle's child is your 2nd cousin (2C).
On the above chart one can see how to locate a 1st, 2nd, 3rd and even a 4th cousin. Therefore, to find our 3rd cousin on our tree, we have to look at our gggrandfather (the orange) who is the father of our ggrandfather and his descendants. Iosel or Josel Symka ben Yankel Goldfus born 1798 should be our common ancestor.
Matching my 1st cousin
TRIANGULATION-on chromosome 2
193,071,967.................................... ...................219,949,518 my daughter(27.9cMs)
193,725,959...............................................................223,565,798 Me ( 33.9cMs)
When you share the same segment with 2 other people, this is called a triangulation.
You use triangulation in seeing who is part of your family.
| Chr | Start Location | End Location | Centimorgans (cM) | SNPs |
| 2 | 28,614,418 | 34,742,899 | 8.6 | 1,844 |
| 2 | 216,044,195 | 241,324,642 | 47.8 | 6,719 |
| 5 | 55,766,345 | 84,196,459 | 30.1 | 6,133 |
| 9 | 134,011,429 | 140,145,149 | 19.5 | 1,893 |
| 10 | 92,947,202 | 101,347,625 | 8.7 | 2,332 |
| 11 | 129,114,448 | 131,952,204 | 8.6 | 1,013 |
| 14 | 42,939,019 | 57,527,999 | 14.5 | 3,564 |
| 17 | 45,683,412 | 51,515,464 | 7.1 | 1,391 |
Total of segments > 7 cM = 144.8 cM
8 matching segments
Estimated number of generations to MRCA = 3.3
Research: https://www.mrsec.psu.edu/sites/mrsec.psu.edu/files/dna_determines_your_appearance.pd
Book: DNA & Genealogy by Colleen Fitzpatrick & Andrew Yeiser
Labels: chromosomes, generations to MRCA, segments
Sunday, January 21, 2018
My Chromosome Bearing Sephardic Jewish Ancestry
We have 23 chromosomes. Scientists have numbered them. The #4 chromosome bears the Sephardic origin segment I match with another female.. I match this person on #1, too. Our common ancestor lived at least 6 generations ago which would take us to about the year of 1868 when my ggrandparents were in Lithuania. The other match has recent ancestors that were Ashkenazic Jews like mine, and were in Poland and Belarus, which were part of the Pale of Settlement. My Ashkenazic ancestors as far as I had discovered were from Poland and Lithuania, also in the Pale.
Jews were in Spain since 70 CE at the time of Rome's destruction of our 2nd Temple in Jerusalem. By 1492 the Spanish Inquisition was in full swing and Jews had to leave the country or convert. Some went underground, hiding their religion from others. Some went to Portugal where a few years later they too had to leave or convert.
To discover that a segment matches someone's Sephardic segment is a new twist to my DNA education. To me, this is amazing ability to pinpoint the origins. Triangulation was used to do so.
We received this Sephardic ancestry segment from Sephardim of Spain or Portugal who have entered into Hispanic communities such as Columbia.
Since I was a little girl, I took dancing lessons. At 4 or 5 I danced a Spanish dance on Battleship Oregon. When I was about 13 I began Spanish dancing lessons from Theresa Stopper in Portland, which included the costuming, high heels and the castanets we clicked away with that were tied to our fingers. That kept up until I graduated high school. Above is more of a Spanish gypsy dance we did. I love both Spanish music and Russian music! It's full of feeling! Maybe it's because I have that teeny bit of a segment from my Sephardic ancestor.
Comparing Kit TIIIIII(LD) and T969950 (Nadene Goldfoot) 5th cousins determined by FTDNA
Minimum segment cM to be included in total = 7.0 cM
| Chr | Start Location | End Location | Centimorgans (cM) | SNPs |
| 1 | 114,686,762 | 145,543,907 | 7.1 | 1,695 |
| 4 | 25,786,470 | 36,779,975 | 11.3 | 1,957 |
Total of segments > 7 cM = 18.4 cM
2 matching segments
Estimated number of generations to MRCA = 4.8
On FTDNA, it looks like this:
| 4 | 26066069 | 36606449 | 9.66 | 1978 |
My son's match to #4 as well. This fits into the perimater of my segment.
| Chr | Start Location | End Location | Centimorgans (cM) | SNPs |
| 4 | 26,961,104 | 36,583,696 | 8.5 | 1,699 |
Total of segments > 7 cM = 8.5 cM
1 matching segments
Estimated number of generations to MRCA = 6.9
On FTDNA, it looks like this:
| 4 | 26982600 | 36063994 | 8.14 | 1678 |
My daughter matches my match on #1 but not #4.She got more SNPs out of the deal than I did, I see though her segment was slightly smaller. Hmmm.
| Chr | Start Location | End Location | Centimorgans (cM) | SNPs |
| 1 | 114,686,762 | 145,448,349 | 7.1 | 1,701 |
Total of segments > 7 cM = 7.1 cM
1 matching segments
Estimated number of generations to MRCA = 7.5
To see if my sibling matched my match, I saw he didn't if I continued to use 7cMs as a minimum to show up, so I changed the tool to show all by using 1 instead of 7. Look what happened.
Here, #4 chromosome is NOT A MATCH. Neither is #1. However, they have matches worthy of a cousin relationship that are 5cMs or bigger. I'll take the 4.9cm segment, too.
| Chr | Start Location | End Location | Centimorgans (cM) | SNPs |
| 1 | 77,039,264 | 80,831,841 | 3.1 | 844 |
| 1 | 106,552,326 | 110,590,348 | 4.4 | 1,019 |
| 2 | 187,918,651 | 190,964,128 | 1.2 | 521 |
| 2 | 194,868,883 | 201,173,536 | 4.6 | 1,102 |
| 3 | 33,883,903 | 36,933,999 | 1.9 | 620 |
| 3 | 102,279,332 | 108,441,535 | 4.9 | 1,213 |
| 4 | 92,881,448 | 96,370,981 | 1.7 | 577 |
| 5 | 99,300,639 | 102,742,754 | 2.2 | 521 |
| 6 | 39,150,312 | 41,839,155 | 5.3 | 849 |
| 7 | 13,996,264 | 15,679,944 | 2.8 | 517 |
| 7 | 98,281,889 | 100,386,197 | 1.2 | 507 |
| 8 | 66,183,286 | 69,205,464 | 2.1 | 549 |
| 9 | 1,257,493 | 2,402,296 | 4.1 | 601 |
| 12 | 41,287,383 | 44,818,128 | 2.5 | 695 |
| 12 | 53,692,096 | 56,891,043 | 2.7 | 678 |
| 12 | 69,230,517 | 72,072,220 | 1.6 | 622 |
| 13 | 60,159,811 | 62,890,418 | 1.2 | 551 |
| 14 | 34,227,935 | 37,250,564 | 3.2 | 645 |
| 14 | 89,491,246 | 91,716,795 | 4.4 | 539 |
| 16 | 72,121,089 | 76,535,568 | 5.2 | 1,239 |
| 21 | 14,743,816 | 16,696,404 | 4.8 | 567 |
Total of segments > 1 cM = 65.2 cM
21 matching segments
Since 2014, I've known that: "One of the latest bits of news about our Goldfus/Goldfoot autosomal DNA test is that it shows a connection to Italy and to the Kalonymus family who were a very famous Italian family who originated from Lucca, Italy and who established themselves in Mainz, Germany. " Could this Sephardic connection be the Kalonymus Italian line?
4/4/18 I've just found out I match another Sepharic lady informed again by researcher and author, Kevin Allen Brook; Castillo from an ancestry (A) test matching on chromosome #16 with 7.8cMs. My son matched on #16 with 8.0cMs and my daughter matched on #16 with 7.8cMs AND #6 with 4.3cMs #16 was the same segment. Then I checked other members of my family. My brother matched #16 with 7.7cMs. A cousin Anthony matched on #16 with 7.8cMs. My daughter in law matched my daughter's match on #6 with 1.4cMs-so small it is not to be considered-not the same segment as my daughter's.
#16 29,066,936.....50,503,620 7.8cMs 786 SNPs My match.
28,458,158.....50,435,924 8.0cMs 823 SNPs son's match
28,949,515.....50,440,889 7.8cMs 788 SNPs daughter's match
29,066,936.....50,435,924 7.7cMs 789 SNPs brother
29,066,936.....50,508,576 7.8cMs 799 SNPs cousin A once removed
#6 70,604,373......75,901,320 4.3cMs 670 SNPs daughter's match
Update: Another match: kit half Ashkenazi and half Sephardi and we match on this chromosome:
| Nadene Goldfoot | 1 | 115697264 | 144976736 | 5.9 |
| 1 | 114,686,762 | 145,543,907 | 7.1 | 1,695 |
Resource: GedMatch.com
Kevin Alan Brook
http://goldfoot_genealogy.blogspot.com/2014/06/autosomal-test-showing-italian.html
Labels: Ashkenazi, dna, segments, Sephardic origin, Spanish dancing, triangulation
Thursday, May 26, 2016
Interesting Facts on Jewish Ashkenazi DNA
On IBDs. Identical by Descent.
Gusev et al (2011) reported that in Ashkenazi Jews “the entire segment of chromosome 6, between 25 and 35 Mb (megabases-a unit of physical distance) , is shared among individuals unrecombined at least 4-fold more than any other region in the genome”.
Peaks of IBD sharing over 5 cMs in size were seen on chromosomes 9 and 19 in Ashkenazi Jews.
AncestryDNA analysed the matches of over half a million US customers genotyped on an Illumina OmniExpress chip (~700,000 SNPs) and found that in certain regions of the genome hundreds and sometimes thousands of people were predicted to share DNA with each other. The problem was particularly pronounced in customers of Jewish ancestry and in some people of Hispanic descent, but the problem was observed across all ethnic groups. They concluded that these regions of identical DNA were likely to be attributed to a shared ethnic history rather than recent common ancestry.
Segment size:
30 cMs 0f a segment stands a 90% chance of coming from 6 generations ago
20-30 cMs 50%
12-20 cMs 20%
6-12 cMs 5%
6 cMs 1%
In a study of a European subset of the Population Reference Sample (POPRES) dataset it was estimated that for the most part IBD blocks
longer than 4 cM come from 500 to 1,500 years ago, and blocks
longer than 10 cM are within the last 500 years.
I"ll look for blocks of 10cMs or more to hope to find a common ancestor. However, "In general it will be difficult to find the genealogical connection with the majority of your matches under about 15 cMs." Then let's hope to find segments of 20 cMs or more for matches.
Resource: http://isogg.org/wiki/Identical_by_descent
The techniques of triangulation, chromosome mapping, and phasing can be used to distinguish between IBD segments and non-IBD segments.
Triangulation was used in the Halpern & Branches group of FTDNA. through GedMatch.com . http://isogg.org/wiki/Identical_by_state
The blog article by Ann Turner, https://segmentology.org/2015/10/02/anatomy-of-an-ibs-segment/, tells how to triangulate. Besides that, it explains much more. One needs to study this.
More on :
http://dna-footprints.com/the-abcs-of-dna-ibd-vs-ibs/.
When we have a DNA segment that matches another person we cannot be sure that it is a real match unless it is also a match to a third person who matches both of us at that spot. This is called triangulation. http://blog.kittycooper.com/2014/10/when-is-a-dna-segment-match-a-real-match-ibd-or-ibs-or-ibc/
So many questions come up with very wee segments that are shared. What does it mean? This is for all people, not just Ashkenazi Jews: http://isogg.org/wiki/Autosomal_DNA_statistics. Below shows the % shared between these distant cousins. These are not even of 1.0cM but less.
| 0.000763% | 0.05cMs | 8th cousins | Degree 17 |
| 0.001525% | 0.10cMs | 7th cousins once removed | Degree 16 |
Small segments are prone to be false positives. What out. There is too much uncertainty surrounding small segments to base any conclusion on them. The researchers found that more than 67% of all reported segments shorter than 4 cM are false-positive segments (see FIG. 2B, below). At least 60% of 4cM segments were false-positive, and at least 33% of 5 cM segments were false-positive. The number of false-positives decreased fairly rapidly above 5 cM.
Labels: Ashkenazis., common ancestors, dna, familyfinder, IBDs, segments
Friday, September 02, 2011
Countries My Genes Are From: My Goldfoot Revelations Found on 23&Me (DNA company)
Labels: country origin, genome, segments






