Wednesday, May 2, 2012

How I traced my ancestry back to the Stone Age

I recently had a genetic test to find out more about where my ancestors came from. The results confirmed what I already knew - I am from a family of European Jews. But there was also a surprise - a Neanderthal forebear. In many families, there seems to be one person who is interested in genealogy. In my family, it's me. When I was 11, I conducted my very first interview with my grandmother, Ray Zall, who graciously answered all my questions about her childhood in Belarus. The recording, which I still have, begins rather grandly: "This is Carol Zall interviewing Ray Zall, my grandmother, or 'Bobe' in Yiddish. Now Mrs Zall, could you tell me about your childhood?" "What can I tell you?" asked my grandmother in her heavily-accented English. "I was born in a small village called Kashuki." I'd never heard of Kashuki. And I still can't find it on a map. "What country is it near?" I asked, confused. "Russian-Poland, Russian-Poland," she answered. My grandmother was born in the early 1900s, in what is now Belarus, but was then Poland (and part of the Russian Empire). Some other ancestors of mine came from similarly vague places in countries that no longer exist, like Austria-Hungary. All of this has made it very hard to trace my roots. Thirty-four years after I recorded that interview with my grandmother, there are new and revealing ways of finding out about your family tree. Advances in the field of genomics have made it possible to use a person's DNA to find out where their ancestors may have come from. A number of companies now offer these tests, and there are a few rules of thumb you can use to separate science from the snake oil. The question is, would this work for me? For about $200 (£125) I signed up with a company called 23andMe (the name derives from the fact that we all have 23 pairs of chromosomes). The next thing I knew I was spitting into a plastic tube and posting my saliva sample to the company. "The first thing we do is extract the DNA from the saliva," says Joanna Mountain, Senior Director of Research at 23andMe. "The DNA gets cut up into little pieces and put on to what we call a chip." Human DNA is like a code made up of three billion letters. Testing companies like 23andMe don't look at all those letters (or positions, as they call them). They look at a small percentage of them - about a million - a process known as "genotyping". The positions are studied to find out all kinds of information - from diseases we may be at risk of in the future, to details about our past. I've always known that my family was Jewish. My entire family tree, so far as I know, consists of European Jews, also known as Ashkenazi Jews. I've always imagined my ancestors as people who spoke Yiddish, lived in Eastern Europe, and listened to klezmer music. However, since Ashkenazis spent centuries wandering around Europe, living among different populations, I've often wondered if they might have married or had children with people who were not Ashkenazi. After all, my mother's mother and all her siblings had red hair and blue eyes. And my own sister - a redhead with freckles - is always assumed to be Irish. A few weeks later, the results of the test came back. "It looks like about two-thirds of it can be traced back to Ashkenazi-Jewish ancestry in Russia, Poland, Belarus, and other nearby countries," says Joanna Mountain. "This is where your Jewish ancestry really pops out," says Mountain as she shows me my chromosomes displayed as separate bars, each one of them covered with bright blue sections, representing all the gene segments I share with other people in her company's database whose known ancestry is Ashkenazi Jewish. __________________ References: Zall, Carol. "How I traced my ancestry back to the Stone Age". BBC News. Posted: April 17, 2012. Available online:

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