Researcher reveals the longest family tree in the world

Have you ever seen or even made your family tree? This graphic representation of family members and all their descendants is used to show connections between individuals and also for medical purposes in order to investigate genetically inherited diseases.

However, making a family tree can be a bit tricky as you need to get data from distant relatives and old generations. Now imagine gathering in a scheme like this the connection of 13 million people? Because a researcher got this done.

Also dubbed the “genome hacker, ” Yaniv Erlich used data extracted from online genealogy sites, building what may be the longest family tree ever assembled. The researcher and his team now plan to use the data - which includes kinship dating back to the 15th century - to analyze inheritance of complex genetic traits such as longevity and fertility.

Study Process

In addition to providing the “guest list” for what would be the world's largest family reunion, the work presented by the computational biologist at the annual meeting of the American Society of Human Genetics in Boston could reveal a new tool for understanding how far genes contribute to certain family characteristics.

So-called pedigree lines were made available to other researchers, but Erlich and his team at the Whitehead Institute in Cambridge, Massachusetts, omitted the names of the participants to protect privacy and cross-linked their information with DNA bank samples.

"The structures of the trees themselves could provide interesting information about human demographics and population expansions, " said Nancy Cox, a geneticist at the University of Chicago, Illinois, who was not involved in the study. She also stated that the most interesting is the possibility that these data may one day be related to medical aspects.

In addition, they would also be linked to DNA sequence information as more people could have their genomes sequenced and deposited in public databases. "We really just started to 'scrape the surface' of what these kinds of lineages can tell us, " said Nancy.

Ancestry and characteristics

The strains provide clues about genetic inheritance. For example, by comparing an individual to his or her most distant relatives in the family tree, the change in frequency of a particular trait, such as fertility, may indicate to what extent the trait exists in its genetic roots.

The tree can also provide clues as to whether the trait is controlled by a few genes that have large effects or by many genes that make minor contributions. However, as was said at the beginning of this article, it takes years to gather genealogical data.

In the past, researchers meticulously gathered this data from church records and individual volunteers. Erlich and his team decided to streamline the data collection process by evaluating over 43 million public profiles on the geni.com genealogy site. Profiles included dates of birth and death as well as locations.

The team gathered the data in family trees that ranged from a few hundred individuals to 13 million people. Despite the researcher's efforts, it is not yet clear how the study results will be used.

However, Kári Stefánsson, founder of a genetic research firm, said this is an incredibly powerful approach and is confident that genealogical analysis will play an important role in genetic studies in the future.