Scientists Find Genetic Signature of Down Syndrome in Ancient Bones

 

    Scientists were able to diagnose Down syndrome using DNA from ancient bones. Down syndrome happens to 1 in 700 newborns today, and it results in an extra copy of chromosome 21. Down syndrome is most likely to occur when older mothers give birth in modern times. Back then, Down syndrome was rare because there were higher chances of women dying young, which made Down syndrome rare. 

    The first Down syndrome case using DNA from ancient bones was in 2020. The bones were found to be of a six-month-old boy who had been buried for almost 5570 years. Scientists also found an infant who had Edwards syndrome. Edwards syndrome is when there is an extra copy of chromosome 18. Researchers believe that the baby was only able to survive up to 40 weeks of gestation. This could possibly be the first case of Edwards syndrome found in the ancient remains. 

This is a picture of ancient remains of infants who had Down syndrome. These bones are about 2500 years old. 

References:

https://www.smithsonianmag.com/smart-news/dna-reveals-presence-of-down-syndrome-in-ancient-society-180983835/

https://www.nytimes.com/2024/02/20/science/down-syndrome-dna-bones.html

Ancient DNA uncovers a hidden chapter in the history of Down syndrome, Blog#6

  Ancient DNA uncovers a hidden chapter in the history of Down syndrome!

Evgeniya Staleva

BIOL- 2100-001- Genetics

Professor Guy F. Barbato

November 27, 2025

 

In the article by Carl Zimmer, scientists were reported to have identified Down syndrome in the bones of seven children, including some over five thousand years old, using ancient DNA. To do this, the team used pieces of genetic material shorter than ten thousand of the bones and wrote a program that counted the number of pieces belonging to a chromosome. The genetic pattern of Down syndrome was evident in bones that contained extra material as a result of chromosome twenty one. One fetus with an extra chromosome eighteen, which is also associated with Edwards syndrome, was also visible on the same screen.

Scientists were unable to determine the prevalence of these disorders in the distant past due to the decay of many infants remains and the loss of many children who did not survive into recorded history. The analysis singles out some of the best burials in the north of Spain. Family members preferred burying babies with Down syndrome and the fetus with Edwards syndrome instead of cremation, and placed them in houses with objects such as jewelry. This pattern is viewed by some experts as possible evidence that such children were treated special and as others warn that with only such a small sample, solid conclusions cannot be made in this initial small study. The technique might also be used to detect numerous other rare genetic diseases in archaeology.

This story is very thought provoking and was quite moving to me. It reveals how genetics have brought back into sight the lost children and the misconception that disability is a problem. The cautious burials led me to visualize parents who cared about their babies and mourned in a manner that resonates with the grief in a modern day. There is a silent lesson in this work to be passed on to a contemporary reader, as well. Individuals with genetic differences have always existed in the human society and our science ought to foster respect, recollection and nurturing of each life.

https://www.nytimes.com/2024/02/20/science/down-syndrome-dna-bones.html

https://pubmed.ncbi.nlm.nih.gov/38378781/

https://www.nature.com/articles/s41467-024-45438-1

Forensics and Cold Cases

 Forensic genetics is a powerful tool used to identify unknown human remains, even decades after death. By analyzing DNA from bones and comparing it to databases, forensic scientists can match remains to missing persons. A prime example is Patricia Ann Hertel, who disappeared in 1981. Her remains were found in 1983 but misidentified as male, and the case went cold. In 2023, forensic genetic genealogy finally led to her correct identification, giving closure to her family.

Another major player is Othram Inc., a lab that uses advanced DNA sequencing to solve cold cases. They've helped identify victims from the 1970s and 1980s by reconstructing DNA from degraded remains and tracing relatives through genealogy databases. While ethical concerns about privacy remain, the ability to restore names to the nameless is an outstanding achievement. 

My Opinion: This is an interesting topic to look into and appreciating the people that put the time and effort into solving these cold cases for closure is needed. 

Sources: Why this Texas lab is so skilled at solving Bay Area cold cases

Skeletal remains identified as Calif. woman in 42-year-old cold case

Remains Identified as Woman Who Disappeared Over 40 Years After Boat Sank