Two weeks ago, we began our look at the information about Jewish genetic disorders on the Internet. Today, how to find information about genetic diseases more common among Jewish communities. Once again, a caution that the Internet should not be considered a substitute for professional medical advice.

The best place to start is at the National Foundation for Jewish Genetic Diseases Web site — www.nfjgd.org The foundation has supplied online information and Web links about genetic diseases more common among Jews, such as Bloom's syndrome, Canavan disease, familial dysautonomia, Fanconia anemia, Gaucher disease, mucolipidosis IV, Niemann-Pick disease, Tay-Sachs disease and torsion dystonia. You can find links to specialized Web sites dedicated to those illnesses at www.nfjgd.org/internet.shtml (I will devote a future article to Jewish genetics, cancer and the Internet.)

Several universities and medical centers have established divisions that specialize in Jewish genetic diseases such as the Albert Einstein Healthcare Network — www.einstein.edu/jewishgenetics — the Jewish Genetic Disorders Program at Chicago's Children's Memorial Hospital — http://jewishgenetics.org — and The Center for the Study and Treatment of Jewish Genetic Diseases at the University of Pittsburgh

— www.pitt.edu/~geneorb/ctr-jewish.html These sites all provide helpful information as does the Mazornet Guide to Jewish Genetic Diseases — http://mazornet.com/genetics

Less known than Tay-Sachs or Canavan disease is the connection between schizophrenia and the Jewish community. The Johns Hopkins University School of Medicine — www.hopkinsmedicine.org/epigen/ashkenazim.htm — wants to identify the susceptibility to schizophrenia among Ashkenazi Jews and develop new treatment.

Why study Ashkenazim? The site explains that "Jewish individuals are in a unique position to assist scientists in the understanding of genetic disorders. Due to a long history of marriage within the faith, which extends back thousands of years, the Jewish community has emerged from a limited number of ancestors and has a similar genetic makeup. This allows researchers to more easily perform genetic studies and locate disease-causing genes."

The site explains that the risks for schizophrenia and bipolar disorder seem to be about 1 percent for any population. Some studies have suggested an increased risk in the Jewish population but those studies have been adequately substantiated at this time.

Sephardim also carry genetic disorders, but as Dr. Gideon Bach of Jerusalem's Hadassah-Hebrew University Medical Center explains, the way these diseases appear is quite different from within the Ashkenazi population. The interview is at www.hadassah.org.il/news/jewish-gen-disease-had0101.htm

"The high-frequency genetic disorders specific to Ashkenazim are different from those of the surrounding populations [Poles, Germans]. Sefardim, however, tend to share hereditary diseases with their host population. This is believed to result not from intermarriage, but from natural selection."

Once you have read through all the Web sites, you may want a personal connection. You can join that worldwide community through e-mail lists such as The Genetic Disease E-Mail Discussion List — www.gaucherdisease.org/list.htm You must supply your name to join the discussion list, but that information will be kept confidential.

Hopefully, the genetic links that join people from around the world will be better understood thanks to links created by the Internet.