How 23andMe identifies your DNA Relatives

Scientific Details

Learn about your DNA Relatives, the diverse group of 23andMe customers who have DNA in common with you. Only individuals who have chosen to participate in DNA Relatives are the subject of this report.

How 23andMe identifies your DNA Relatives

To identify your DNA Relatives, we use an algorithm that finds segments of your DNA that are identical to DNA segments of other 23andMe customers. When these segments are sufficiently long, we infer that they were inherited from a recent common ancestor. These segments are known as “identical by descent,” or IBD. Our algorithm searches for these matches across virtually your entire genome, so we can identify DNA Relatives on any branch of your family tree.

Note: IBD/Half IBD:

The comparison results in this feature displays shared segments of DNA on separate lines representing each chromosome pair, and labels the shared segments as Half IBD, or identical by descent. Because you inherit one half of your DNA from your mother and the other half from your father, IBD segments typically occur on only a single chromosome. Half IBD refers to the amount of the genome in centiMorgans (cM) that contains an IBD segment on either chromosome. The percent DNA shared in DNA Relatives is based on this number.

Your half IBD and shared segments vary based on the closeness of your relationship with the matches with whom you are comparing. Closer relatives will share thousands of cM and many segments in common; more distant relatives may share only one. For some of your shares, if you connected outside of DNA Relatives, you may not share any segments at all.

Every time DNA is passed from one generation to the next, the two chromosomes in each pair are randomly shuffled with each other in a process called recombination. Then, only half of this new DNA — one set of chromosomes — is passed down to each child. The total amount of DNA passed down from an ancestor is cut approximately in half each generation. Through this process, long inherited segments are broken up generation by generation into multiple shorter ones and sometimes lost altogether.

Despite all of this generational shuffling, DNA Relatives is highly sensitive and can pick up matches ranging from siblings and uncles to distant eighth cousins — individuals that share great-great-great-great-great-great-great grandparents with you. It may not always be obvious how you share a connection with someone, but that’s where our DNA Relatives tool comes in. Visit the tool to find out more about your matches and get in touch to learn about your family history.

See our Customer Care pages for more information:

Shared segments between cousins

Inheritance family tree graphic.

A closer look at the matching segment

An example graphic showing a matching segment between you and your cousin.

Sources of information used in this report

The Your DNA Family report provides aggregated summaries of several attributes of your DNA Relatives. The following information sources are used in the report:

Report Section
Source
Close to distant DNA Relatives

Computed IBD results from the DNA Relatives tool.

Locations of your DNA Relatives

Answers to survey questions by your DNA Relatives.

Ancestries of your DNA Relatives

Computed results from the Ancestry Composition report.

Traits and behaviors in your 23andMe DNA Family

Answers to survey questions by your DNA Relatives.

Traits in Your DNA Family

Henrietta Lacks Story NIH

 

 

 

Archives of Maryland
(Biographical Series)

Henrietta Lacks (1920-1951)
MSA SC 3520-16887

Biography:

Despite living a very short life, Henrietta Lacks is one of the most important people in the history of medicine. Lacks’ cells, known as the HeLa cell line, are mysteriously immortal and have been used by scientists and researchers all over the world to study and develop cures for a plethora of diseases. For decades, Lacks and her family were not given any recognition for her contribution to the medical field, but, in recent years, Henrietta Lacks’ legacy has been credited for saving the lives of millions.
Henrietta Lacks was born as Loretta Pleasant in Roanoke, Virginia in August 1920 to Johnny and Eliza Pleasant, both African American. No one is aware when she changed her name to Henrietta from Loretta. Lacks’ mother died when she was only five, and she was then sent to live in Clover, Virginia with her grandfather in a log cabin that was previously the slave quarters on her white great-grandfather’s plantation.1 While slavery was still legal, Lacks’ white great-grandfather took a slave mistress, thus starting Henrietta’s family line of black Lackses.2 When she was old enough, Lacks began farming tobacco on the plantation like the rest of her family.

Lacks gave birth to her first child soon after her fourteenth birthday, and the father of the child was her first cousin, David “Day” Lacks.3 Henrietta and Day named their first son Lawrence and, four years later, Lacks gave birth to her second child and first daughter, Eliza. On April 10, 1941, Henrietta, age 20, married Day, age 25. Soon after their marriage, Day moved to Baltimore to take advantage of the large amount of opportunity in the steel factories during World War II, and Henrietta and the two children soon followed.
While living in Baltimore, Henrietta gave birth to three more children. She “spent her time cooking for Day, the children, and whichever cousins happened to be at her house. She made her famous rice pudding and slow-cooked greens, chitlins, and the vats of spaghetti with meatballs she kept going on the stove for whenever cousins dropped by hungry.”4 One of her friends reflected that “Hennie made life come alive—bein with her was like bein with fun. Hennie just love peoples. She was a person that could really make the good things come out of you.”5 Although Henrietta Lacks held the ability to make the good come out of people, something lethal was growing inside her body. She began telling her family and friends that she had a knot in her womb or that she was bleeding even though it was not her time of the month.6 After feeling something strange on her cervix, Lacks knew it was imperative for her to go visit a doctor.
Lacks made an appointment at The Johns Hopkins Hospital in Baltimore and her biopsy results determined that she had Stage I epidermoid carcinoma of the cervix, or cervical cancer. The doctor that examined her found it incredibly interesting that even though she had no cervical abnormalities when she delivered a baby at Hopkins three months prior, she now returned to the hospital with a cancerous tumor.7 After the mass was diagnosed as cancerous, Lacks was instructed to return to the hospital to begin radium treatment. Radium was known to cause cancer, but it was also known to kill cancer. Unfortunately, it was also known to burn the skin, which is exactly what happened to Lacks during her treatment. Those close to her were horrified when Lacks confided in them the damage from her treatment, telling them that “Lord it just feels like that blackness be spreadin all inside me.”8
That “blackness,” her cancer, was actually spreading all inside her. In August 1951, Lacks returned to Hopkins, asking to be admitted because her pain was unbearable. She died a grim death on October 4, 1951 at age 31 from cancer that had metastasized throughout her entire body. Lacks was buried in a wooden box in an unmarked grave in Clover, Virginia. What Henrietta Lacks and her family did not know, however, was that she would live on forever through her cells. During her cancer treatment at Johns Hopkins, her doctor took healthy and cancerous samples from Lacks’ cervix without informing her of his actions or getting consent from her, and gave them to George Gey, a cancer researcher.  This was standard practice, and, at the time of Lacks’s death, there were no state or federal laws regarding obtaining consent from any patient.9 Gey was constantly analyzing human cells in an effort to create the perfect culture medium, or the liquid used for feeding cells. After being placed in a Petri dish, the cells would usually die within a few hours, but Gey found that Henrietta’s cells did something amazing. Her cells kept reproducing.
Gey started his own cell line, which he named HeLa in tribute to Henrietta Lacks. Neither Gey nor his assistant revealed the name of the original owner of the immortal cell line, thus making Lacks’ name unknown to the public. The medical breakthroughs from the usage of HeLa cells quickly began after Lacks’ death. A scientist named Jonas Salk proclaimed that he had found a cure to polio but needed to test the vaccine first. Salk acquired some HeLa cells, and, in 1954, Salk released the vaccine that prevented polio. Millions of lives were saved from this disease, thanks to the testing performed on the HeLa cells.
Since Gey did not patent his HeLa cells, labs all over the world soon began obtaining these unique cells for research and experiments. HeLa cells even went to space when the United States wanted to test how human cells would react in zero gravity, and were used to determine the affects of the atomic bomb.10 Scientists used HeLa cells to study molecular biology, virology, and genetics. Lacks’ cells were also used for research on cancer, AIDS, and, more recently, Human Papillomavirus (HPV) and In Vitro Fertilization (IVF). Vaccines and drugs for diseases such as herpes, leukemia, influenza, hemophilia, and Parkinson’s disease were also developed through testing done on HeLa cells.
Henrietta Lacks’ cells were being used to make scientific breakthroughs beyond many researchers’ wildest dreams, but her family was unaware of Henrietta’s contribution to science. In 1953, a reporter at the Minneapolis Star claimed that the HeLa cells belonged to a woman named Henrietta Lakes, alerting people for the first time that these were human cells.11 Other reporters claimed that HeLa stood for Helen Lane or Helen Larson.12 Either way, the name Henrietta Lacks was never published, and the Lacks family was unaware that Henrietta’s cells were being circulated around the globe until 1973.

One day in 1973, Bobbette Lacks, Lawrence’s wife, was having lunch with her friend and her friend’s brother-in-law. The brother-in-law and Bobbette discovered that they were from the same part of Baltimore, and Bobbette told him that her last name was Lacks. Her friend’s brother-in-law told Bobbette that he worked at the National Cancer Institute and that he had been working for years with cells in his lab that he just recently learned belonged to a woman named Henrietta Lacks. Bobbette soon learned that this man, like many others around the world, had her mother-in-law’s cells in their labs.13 Thus began the anger, confusion, and frustration that would consume the Lacks family for decades.
The Lacks family, still living in Baltimore City, was impoverished and in poor health. They were being harassed by doctors and researchers for blood samples and developed a serious mistrust of Johns Hopkins Hospital. They felt that they had been robbed by Hopkins and thought that Henrietta was still alive and her body was being held hostage in the hospital. Some members of the family thought that suing the hospital for taking a part of Henrietta without her consent or knowledge was the proper path, but they would soon learn their case was fruitless. Around the same time the Lacks family discovered the truth about the HeLa cells, a Californian man named Roger Moore was attempting to sue his doctor for unknowingly scraping his cells and profiting from them. The case finally reached the Supreme Court of California, and the court ruled that “When tissues are removed from your body, with or without your consent, any claim you might have had to owning them vanishes. When you leave tissues in a doctor’s office or a lab, you abandon them as waste, and anyone can take your garbage and sell it.”14 This ruling set a precedent, stripping a large amount of power away from patients and legally allowing doctors and researchers to financially exploit their patients if they discovered something medically groundbreaking. This opened a global debate about bioethics, but also left the Lacks’ family without a legal case.
In 1997, the British Broadcasting Corporation (BBC) came to Baltimore to interview the Lacks family for a documentary about the HeLa cells’ role in cancer research. This gained some publicity about the woman behind the HeLa cells, and, in the same year, then United States Representative Robert L. Ehrlich, Jr. formally addressed Congress about Lacks, saying that “Henrietta Lacks’ selfless contribution to the field of medicine has gone without acknowledgement for far too long. Her cells made her immortal: through her death, countless others have been saved by the research that was made possible through her cell line…I sincerely hope her name will also be immortalized as one of courage, hope, and strength, and that due recognition will be given to her role in medicine and science.”15 Henrietta’s enormous contribution to decades of science was recognized, but true justice for Henrietta still seemed hopeless.
Hope came to the Lacks family a few years later in the form of a young, white, female writer named Rebecca Skloot. Skloot became fascinated with the mystery behind the HeLa cells at age sixteen and spent many years trying to uncover the story behind the immortal cells. The Lacks, understandably, were mistrusting of Skloot and her motives. Skloot, however, proved to be faithful to the family in regards to spreading their story, and she became the closest with Henrietta’s daughter, Deborah. Deborah never knew her mother but always wanted to understand what happened to her. Through Deborah, Skloot was able to better understand the struggles of the family and tell the story of Henrietta, and through Skloot, Deborah was able to learn about her mother and even hold her cells. Skloot published The Immortal Life of Henrietta Lacks in 2010 and describes the book as “not only the story of HeLa cells and Henrietta Lacks, but of Henrietta’s family—particularly Deborah—and their lifelong struggle to make peace with the existence of those cells, and the science that made them possible.”16 The novel became an instant best-seller and was even comissioned by Oprah Winfrey to be made into a movie. The Lacks family was finally given the recognition they struggled for years to gain.
In 2013, 62 years after Henrietta’s death, the Lackses were finally able to have a voice in the distribution of HeLa cells. Controversy began again in early 2013 after a German lab published the HeLa genome in an online magazine. The German research lab published the paper “to show the degree to which the genomes of HeLa cells diverged from those of healthy cells, so researchers could take that into account when designing experiments and analyzing results from studies using the HeLa cell line,” but the Lacks family worried that others would be able to formulate their genetic codes through this public information.17 The article was taken down, but the Lackses still felt their biological information was being distributed without their consent and that “history was repeating itself” since anyone could get a hold of Henrietta’s genomes.18 In August 2013, an agreement between the Lackses and the National Institute of Health (NIH) was formulated, decreeing that scientists had to obtain permission from the NIH in order to conduct research on HeLa cells. The NIH and two members of the Lacks family would approve or reject the applications as they saw fit. Finally, the Lacks family could stop the outright exploitation of Henrietta.
Henrietta Lacks did not live a long life, but her cells will live on forever. She has had a greater impact on science than any other scientist or researcher will ever claim, and her cells have been used to save the lives of a countless number of people and animals. As the most important person in medicine, and as a former Maryland resident, Henrietta Lacks will be immortalized as an important Maryland woman through her induction into the 2014 Women’s Hall of Fame.

 

  1. Henrietta Lacks Women’s Hall of Fame 2014 Nomination Packet. Return to text
  2. “The Way of All Flesh,” Adam Curtis, available on YouTube: https://www.youtube.com/watch?v=C0lMrp_ySg8. Return to text
  3. Rebecca Skloot, The Immortal Life of Henrietta Lacks, (New York: Crown Publishers, 2010), 23. Return to text
  4. Ibid, 42. Return to text
  5. Ibid, 43. Return to text
  6. Ibid, 15. Return to text
  7. Ibid, 17. Return to text
  8. Ibid, 48. Return to text
  9. Alok Jha and Rebecca Skloot, “The ‘immortal’ Henrietta Lacks–Science Weekly,” podcast audio, The Guardian: Science Weekly, accessed June 25, 2014, http://www.theguardian.com/science/blog/audio/2010/jun/21/science-weekly-podcast-henrietta-lacks-rebecca-skloot?commentpage=1. Return to text
  10. Henrietta Lacks Women’s Hall of Fame 2014 Nomination Packet. Return to text
  11. Skloot, The Immortal Life of Henrietta Lacks, 105. Return to text
  12. Ibid, 109. Return to text
  13. Ibid, 180. Return to text
  14. Ibid, 205. Return to text
  15. Robert L. Ehrlich, Jr., “In Memory of Henrietta Lacks” (June 4, 1997), Congressional Record Volume 143, Number 75, https://beta.congress.gov/congressional-record/1997/06/04/extensions-of-remarks-section/article/E1109-1.  Return to text
  16. Skloot, The Immortal Life of Henrietta Lacks, 7. Return to text
  17. “German lab apologizes for publishing the genome of ‘immortal’ woman’s cell line,” Washington Post, April 2, 2013. Return to text
  18. Andrea K. Walker, “Lacks’ kin finally get say in use of her cells: After decades, NIH accord requires permission to use her genome in research,” Baltimore Sun, August 8, 2013. Return to text

Biography written by 2014 summer intern Sharon Miyagawa.

Return to Henrietta Lacks’ Introductory Page

 

This information resource of the Maryland State Archives is presented here for fair use in the public domain. When this material is used, in whole or in part, proper citation and credit must be attributed to the Maryland State Archives. PLEASE NOTE: Rights assessment for associated source material is the responsibility of the user.

Genetic Genealogy for Beginners – Chapter 3

 

 

Y-DNA Explained

Almost every article I have read on Genetic Genealogy, there have been comments or reviews from readers stating their frustration and confusion understanding the literature by well intended authors.

This chapter will began to focus on Y-DNA testing, which is the oldest test. Before we get started, lets look at your goals for testing to make sure you are clear. I suggest you write out your goals.

Do you have a general idea or just a curiosity about genetic genealogy or is your focus more specific? Consider the following questions:

  • Are you primarily interested in researching your surname?
  • Are there specific brick walls (you feel you can not  research further) that you wish to target with the use of DNA testing. (African-American getting beyond 1860)
  • How far back in your family tree are these brick walls? (This is a serious question for African-American genealogy researchers.)
  • What is the ancestral pattern back to these walls, i.e. – mother’s mother’s mother’s, mother or father’s mother’s mother’s father’s, father’s father’s father?
  • Are you ready for a long-time project or do you desire quick answers? (Long-time projects are best suited for this type of work. Quick answers tend to create mistake after mistake.)
  • Are there adoptions in your family tree that you would like to explore. (this is another heavy one for African-Americans. A lot of slaves could not read, write or speak English clearly who became free after the Civil War down south and north as well. Many migrated North and West looking for work and places for their families leaving their children with friends, neighbors or just disappearing under unusual circumstances. The people that kept theses children change their names or adopted them unofficially. Example: John Wilson and his family on the plantation may have changed to Amos Myatt and family. The DNA did not change. Understanding this and working through this is a challenge to any African-American researcher. This takes a real slow process of researching and genealogical detective work to find the connection.
  • Is your primary interest receiving a percentage breakdown of your ancestral origins or “Ethnicity”?

Currently there are tests geared at isolating types of DNA that can address these questions and others. They are the Y-chromosome DNA (Y-DNA), mitochondrial DNA (mtDNA) and the autosomal DNA (atDNA). Y-DNA has been in use the longest and has the best track record for helping genealogists demolish those proverbial brick walls.

Y-DNA refers to the DNA found on the Y chromosome. Only males inherit the Y chromosome, so this test can only be used to trace the direct paternal line. A father inherits his Y chromosome from his father who inherits it from his father who inherits it from his father and on and on. Ancient origins of a person’s direct paternal line.

Example from Ancestry.com DNA test results my line. Johns’ family paternal line.

Unlike all other chromosomes, the Y chromosome does not undergo extensive recombination before it is passed down to the next generation. There can be some recombination between the two tips of the Y and X chromosomes, but those regions are not used for genetic genealogy.

 

The unique inheritance pattern of Y-DNA offers both advantages and limitations when applying test results to a genealogical problem. The lack of recombination means that the same Y-DNA footprint is passed down for many generations, allowing a line to be traced many generations back in time. The fact that the same Y-DNA footprint is passed down for many generations is a major advantage when trying to determine if a patrillineal line was a specific biogeographical origin, such as African or Native American. The origin-identifying markers will not be diluted by recombination and will persist through all generations.

Types of Y-DNA Testing

There are two main types of Y-DNA testing for genetic genealogy: Short Tandem Repeat (STRand Single Nucleotide Polymorphism (SNP).  

These test look at different kinds a markers, provide different information, and have different uses and limitations. I will take up more on this subject in the intermediate and advanced chapters at  later time.

 

 

 

 

DNA Replication

 

 

This 3D animation shows you how DNA is copied in a cell. It shows how both strands of the DNA helix are unzipped and copied to produce two identical DNA molecules.

Source:

http://www.yourgenome.org/video/dna-replication

access 1/28/2017

 

Haplogroup

 

The Legal Genealogist: Term of the day: haplogroup

 

Source: http://thelegalgenealogist.com dated 22 Feb. 2017

This article was written from a Eurasian perspective. The definitions are correct.
The genetic genealogy glossary defiunition of haplogroup is “a genetic population group of people who share a common ancestor on the patrilineal or matrilineal line. Haplogroups are assigned letters of the alphabet, and refinements consist of additional number and letter combinations.”1

Okay. Great. What’s that mean?

Basically, if you think of all humans who’ve ever lived as part of the human race as a family tree, our haplogroup is what branch of the tree we can park ourselves on.

Everybody — male and female — has at least one haplogroup: our maternal haplogroup, as defined by our mitochondrial DNA (mtDNA). That’s the kind of DNA we all inherit from our mothers and that only females pass on to their children.2Our mtDNA haplogroup, then, is the branch of the tree we’re sitting on when the roots go back to the first woman from whom we descend: our mother’s mother’s mother’s mother.3

By itself, the mtDNA haplogroup tells us a great deal about our very deep ancestry many generations, even thousands of years in the past. But it also has some information we can use right now. It can tell us, for example, if our direct maternal line is of recent African or Native American origin. Or whether you, like me, have a maternal line that’s plain vanilla European.

Note that the fact that my maternal line is plain vanilla European doesn’t rule out having some more interesting ancestor from Africa or with Native American origin — it just means it isn’t my direct maternal line. It’s not in the direct line from my mother’s mother’s mother’s mother.

Only one of the major genetic genealogy companies offers mtDNA testing: Family Tree DNA. When you test at the HVR1 or HVR1+2 levels, the test looks at enough of the genetic markers to tell you what broad branch you belong to, represented by a letter like K or H. To get the specific branch — or twig! — the full mitochondrial sequence test (FMS) tests the entire mitochondria.4

Men also have another haplogroup, carried in their YDNA. That’s the kind of DNA that only males have and that’s passed from father to son largely unchanged through the generations.5 The YDNA haplogroup, then, is the branch of the tree a male is sitting on when the roots go back to the first man from whom he descends: his father’s father’s father’s father.6

By itself, the YDNA haplogroup tells the tale of deep ancestry just as the mtDNA haplogroup does, can indicate specific types of recent ethnicity — and is particularly useful genealogically to help distinguish between groups of men of the same surname: in my own research, for example, we thought our Shew line might be related to a specific Pennsylvania Shew line until we found that our line was haplogroup I and the Pennsylvania line was haplogroup R. Different branches of the human family tree entirely.

You will get a prediction of your YDNA haplogroup when you test with 23andMe and can get very specific YDNA haplogroup data from YDNA testing with Family Tree DNA, the only major genetic genealogy company that offers YDNA tests.


SOURCES

  1. ISOGG Wiki (http://www.isogg.org/wiki), “Haplogroup,” rev. 27 Dec 2016.
  2. Ibid., “Mitochondrial DNA tests,” rev. 15 Jan 2017.
  3. And so on back into time, often well before genealogical time. And see ibid., “Mitochondrial DNA haplogroup,” rev. 24 Sep 2017.
  4. Ibid., “Haplogroup,” rev. 27 Dec 2016.
  5. Ibid., “Y chromosome DNA tests,” rev. 4 Dec 2016.
  6. And so on back into time, often well before genealogical time. See also ibid., “Y-DNA Haplogroup ages”, rev. 19 Oct 2013.
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