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Friday, May 12, 2023

Our Genes Tell The Story On Mother's Day

                        You've all heard by now of DNA.  It's something that's unbelievable but real though we can't see it.  Every child we have comes with DNA from you and your other half.  Let me tell you how special this DNA is.  

The DNA most important to us is autosomal DNA.  "Autosomal DNA tests, such as those sold by AncestryDNA, 23andMe, MyHeritage DNA, Family Tree DNA, and Living DNA can provide information about a broad portion of our ancestors going back as far as about 1000 years, and sometimes a bit more."  Our actual long distance DNA has been traced back thousands of years. So science can tell us where our ancestors lived born a 1,000 years ago !  

DNA stands for deoxyribonucleic acid (de-oxy-ribo-nucleic) acid which is the blueprint for life.  It is the sequence of chemicals that creates us all, making us unique from others, yet similar.  It looks like a double helix.  It's in each cell of our bodies.

Human DNA contains 3,147 million chemical nucleotide bases, made up of (A,G,C,T.)                         

    Remember that Earth is 3rd planet from the sun? Or 93.892 million mi.?  An insignificant dot in the picture above?  The total length of DNA present in one adult human is about 2 x 10 to the 13th power meters, the distance from the earth to the sun and back.

The DNA in an average chromosome is about 5cM long.

The basic unit of heredity passed from parent to child is in every one of our cells. Genes are made up of sequences of DNA and are arranged, one after another, at specific locations on chromosomes in the nucleus of cells. Each of us have 30,000 genes.  The average gene consists of 3,000 bases.  Sizes of genes vary greatly, with the largest known human gene consisting of 2.4 million bases, those 4 A,G,C,T letters.

To think that our body, our cells understand all this scientific stuff is too amazing when our minds can hardly take it all in.  Sometimes they do make a typo and we have a mutation that seems to work for the scientists for that's how they trace the different limbs of the tree of life.  

"The unique structure of chromosomes keeps DNA tightly wrapped around spool-like proteins, called histones. Without such packaging, DNA molecules would be too long to fit inside cells. For example, if all of the DNA molecules in a single human cell were unwound from their histones and placed end-to-end, they would stretch 6 feet."  

We each have 23 chromosomes where these genes all sit.  I see the chromosomes like the rungs on a ladder.  The last one, the 23rd, is named as either X or Y.  X means females and Y means males. So, The major function of chromosomes is to carry the hereditary information from one cell generation to the next. DNA is the only permanent component of the chromosome and is the sole genetic material of  Eukaryotes (a cell)  


 Each chromosome has several genes that code multiple proteins.

We may not be very smart, but at least our body responds to all of this scientific mumbo jumbo.  Think of that!  the process of making a human is a most complicated enterprise.  We're an even mixture  of our mother and our father's genes that they passed onto us.     

Born With Label Telling Where Manufactured and By Whom

The best part of what the cells contain, this marvelous DNA, is its haplotype.  Women's haplogroup is found( mt) or (mitochondria) is found around the nucleus of the cell, on the outside of it.  Men's haplogroup is found (Y) or Nuclear DNA) is found in the center of the cell.  That's where they harvest that information which is so important.    

 What it amounts to is coming into this world with a label telling us who their male family line is;  the branch or even the twig off a branch of the tree of life.  My father's Y haplogroup is Q, and after the newest test (Big Y) shows his label reads as QBZ67.  If there are any other men with this label, they are closely related. We're a Jewish group who branched off the native Americans of north and south America long long ago and wound up in Israel.  I believe Turkey was a turning point on the journey.   

My mother's MT haplogroup line is H, now named Helena by Bryan Sykes, researcher of women's lines who has found the 7 basic "Daughters of Eve."  He explains that the original Helena lived 20,000 years ago during the last ice age.  Mom's mother was a Swede, so this connects telling about the glaciers and permanent ice fields covering all of Scandinavia, stretching south to Berlin and Warsaw.  

Below; my mother and myself;  I inherited my eyes from my father's side of the family and a lot more of his genes, but not his tag of Y haplogroup.  To know that I had to have my brother tested.   A man carries both the Y and the MT haplogroup tags.                                                         




                               Lauren Bacall b: 1924 and her mother
Lauren Bacall  born Betty Joan Perske; September 16, 1924 – August 12, 2014)  Lauren Bacall was born Betty Joan Perske on September 16, 1924, in the Bronx, New York City, the only child of Natalie (née Weinstein-Bacal; 1901–1969), a secretary who later legally changed her surname to Bacal, and William Perske (1889–1982), who worked in sales. Both of her parents were Jewish. Her mother emigrated from IașiRomania through Ellis Island. Her father was born in New Jersey to parents who were born in Valozhyn, a predominantly Jewish community in present-day Belarus. (I have 3rd and 4th cousins who are Weinsteins. )  
Latvia, Lithuania, Belarus, Ukraine, Poland, Moldova--all part of Pale of 
Settlement held by Catherine the Great of Russia (my relatives)

The 1st chromosome, #1, has the most known genes (2,968) 
and the Y-chromosome (#23) has the fewest (231).  

As of 2005, scientists were in the dark as to the functions for over 50% of identified genes. 

                          Throwing tantrums

So much of what we do is some aspect of our behavior passed onto us by our ancestors through our genes.  Our behavior can be affected, altered by our environment, again, depending on the genes within us who hold the power to do so.  In a way, we're like machines that have artificial intelligence--they are a good copy of us.  The fact is that we're still 100% better than the artificial intelligences because something within that artificiality doesn't have the little voice within telling it that it's not the thing to do. Actually, a few of us humans seem to be born without it, too. 

Out of my 23 chromosomes, I found sharing with  a deceased  distant cousin of mine...This is from Gedmatch.com.  cMs are the most important to me.  This is how long the gene segment is. Chromosome #1, has 2 long segments (7.5cM and 7.7cM)  # 15 had a good lengthy segment, too.  This connection goes pretty far back, and segments often tend to lose parts of themselves after undergoing another generation of life.  Notice that we share 3 different segments on chromosome #1 !  There are 4 different segments on chromosome #4.   Comparing Kit ... (Nadene Goldfoot) [Migration - F2 - F] and ...

ChrB37 Start Pos'nB37 End Pos'nCentimorgans (cM)SNPsSegment thresholdBunch limitSNP Density Ratio
163,457,25969,909,5127.51,5731851110.46
1207,596,484210,055,63046832061230.45
1243,028,780245,774,9937.76251961170.42
2129,835,103133,541,45455501871120.46
2218,803,329220,639,6963.13842051230.45
38,729,55110,566,9403.65921931150.48
371,872,01473,111,9983.13531941160.44
3115,775,346117,794,2843.55202031210.47
3140,160,906142,652,5593.24892281360.45
4140,724,600145,520,6084.67301931150.39
4164,007,992167,099,9164.26871961170.43
4184,394,392185,330,6693.22961851110.41
5172,268,003173,151,17132761831090.45
5173,160,609174,295,2094.13631861110.44
65,659,4788,260,3366.18971821090.47
7153,522,140154,681,3834.13272021210.38
88,374,43911,860,84541,2121871120.47
8127,339,929128,858,0414.24401961170.42
8137,604,801139,149,4063.33811811080.44
927,630,41834,437,4696.21,5312011200.46
988,118,23790,203,2214.25041741040.49
1253,552,47556,349,83645761851110.48
1432,343,67133,530,0574.43511911140.42
1557,116,17860,883,2817.11,0681921150.44
1610,039,35711,481,8453.34781821090.46
173,719,6205,945,8765.16522161290.46
1755,110,71059,307,71357112151290.44
1773,611,82374,958,4523.13172091250.42
183,928,6364,836,27033302021210.45
198,285,6079,246,2053.42512031210.44
206,764,5367,951,6563.23111961170.42
2020,371,40625,055,4453.91,0452081240.47

Largest segment = 7.7 cM                       

A scientist at the Max Planck Institute for the Science of Human History looks at a jaw bone. Bone, soft tissue and teeth were all studied as part of the research.

When archaeologists were finding pharaohs in Egypt, they finally were able to test for DNA, and found that some still could be harvested from a tooth's roots.  The easiest haplogroup to find was the MT haplogroup (of women's line).  It's harder to retreive the male line of Y haplgroup.  This is the exciting part of genealogy.  

Previous DNA analysis of mummies has been treated with a necessary dose of skepticism, explains professor Johannes Krause of the Max Planck Institute.

“When you touch a bone, you probably leave more DNA on the bone than is inside (it),” he argued. “Contamination is a big issue. … Only in the last five or six years has it become possible to actually study DNA from ancient humans, because we can now show whether DNA is ancient or not by (its) chemical properties.”

Heat and high humidity in tombs, paired with some of the chemicals involved in mummification, all contribute to DNA degradation, the paper adds, but it describes its findings as “the first reliable data set obtained from ancient Egyptians.”

Analyzing samples spanning over a millennium, researchers looked for genetic differences compared with Egyptians today. They found that the sample set showed a strong connection with a cluster of ancient non-African populations based east of the Mediterranean Sea.

Resource:

Book: DNA &o Genealogy b Colleen Fitzpatrick & Andrew Yeiser

 

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