Tales of Genetic Insularity
Posted by Izhar Groner on
A Silicon Valley entrepreneur was once asked to describe his Israeli partner. He said, “Like all Israeli men, he is short, intense, and balding.”
I laughed out loud because it was an apt description of me and many of my Israeli friends and family.
Within each Jewish diaspora (Ashkenazi, Syrian, Irani-Iraqi, Greek-Turkish…), members of the Jewish community, on average, are genetically related to each other as 4th or 5th cousins are, with some evidence of multiple lineages of more remote relatedness.
My own diaspora, Ashkenazi (Central-Eastern European), is close-knit enough that my wife and I had to undergo a test for Tay-Sachs before getting married.
Tay-Sachs is a genetic mutation that eliminates an enzyme that breaks down gangliosides, a fatty substance. This substance then builds up in the nervous system, resulting in childhood seizures, paralysis, and eventual death.
Tay-Sachs is found in the gene pools of Ashkenazi Jews, some French Quebecois, the Louisiana Cajun community, and Pennsylvania’s Old-Order Amish. This clustering corroborates other genetic findings about the origin of Ashkenazi Jews.
These genetic findings point to a small Jewish settlement in the Rhine Valley between the 5th and 10th centuries CE. During this period, about 40% of the Jewish men took local German wives who converted to Judaism. Altogether, by the 10th century, this community numbered in the few hundreds, and it was the founding population of Ashkenazi Jewry. They went on to migrate to Central and Eastern Europe, and remained genetically isolated on the whole.
In Pennsylvania, in addition to Tay-Sachs, some Old-Order Amish suffer from a genetic mutation called Ellis-van Creveld syndrome (EVC) which is expressed in polydactyly (having 6 fingers or toes), bone and heart malformations, and other conditions.
The most inbred of all were probably the Habsburgs of Spain.
They interbred for political reasons. One of their signature features was their protruding lower jaw, which became known as the “Habsburg Jaw.” Their last scion, King Charles II, had it so badly that between his jaw and oversized tongue he had difficulty eating, breathing, and speaking, and even found it hard to keep his jaw up, walking around with his mouth wide open. He suffered from epilepsy, mental retardation, and a slew of other diseases. His father was the uncle of his mother. Since they were closely related, Charles II had the same inbreeding coefficient as the offspring of two siblings. He died in 1700 at the age of 38.
Last week, I received a call from a gentleman who borrowed capital from me in my previous life in finance. He is originally from Thessaloniki, Greece, and he carries a genetic mutation that is common in that area, a form of anemia called Beta Thalassemia. He doesn’t have enough hemoglobin to shuttle sufficient oxygen during exertion, so he doesn’t exercise at all. Between that and his sweet tooth, he is pre-diabetic. When he saw my products he was so excited that he immediately placed an order.
I can’t do anything about his underlying condition, but my products will make him feel satiated, helping him in averting diabetes. That will be tremendously rewarding for me.
If you are reading this post, you must have a genetic predisposition to intellectual occupation, i.e., sitting in front of a computer all day. To help you with this condition, we are offering nutritious snacks that you will royally enjoy, at plantraw.com.