Saturday, January 22, 2005

Quiet Eugenics Nearly Eliminates a Deadly Disease

Tay-Sachs is a inherited disease that causes the rapid degeneration of the central nervous system. It is always fatal. Children born with Tay-Sachs suffer terribly and rarely live beyond their fifth birthday. Like many other inherited diseases - i.e. sickle cell anemia, cystic fibrosis - Tay-Sachs is mostly confined to a specific ethnic group - in this case, Ashkenazi Jews. Tay-Sachs may also be the first genetic disorder almost totally eliminated by voluntary eugenics.
Some 1,000 years ago a Jew developed the genetic mutation which, it turned out, causes the fatal inherited disease. It has since been passed on among the Jewish people through the generations.
Tay-Sachs occurs when an individual does not produce an enzyme called hexosaminidase A (Hex-A), which prevents the build up of a lipid - GM2 ganglioside - inside cells. Unchecked accumulation of this lipid causes acute cellular damage, particularly in nerve cells. Hex-A production is controlled by a pair of genes located on chromosome 15. Tay-Sach results from a mutation which renders one of the pair of genes inactive. So long as one gene is active, Hex-A is produced and the person remains healthy. However, if two individuals carrying the Tay-Sachs mutation - one inactive Hex-A gene - produce a child, that child may inherit two inactive genes, in which case, the body will not produce Hex-A and the child will have Tay-Sachs disease.

The fact that two parents carry the inactive gene doesn't mean that all their offspring will have the disease, of course. In the mathematics of autosomal recessive genetics, such a couple has a 25 percent chance of giving birth to a child with Tay-Sachs, a 50 percent chance of producing a child who will carry the gene, but never suffer the disorder, and a 25 percent chance of producing a child who niether has the disease nor carries the mutated gene. This genetic lottery pertains to every child the couple produces.

However, modern science and rational decision-making may have brought an end to this nightmare.
"Last year not a single Jewish baby throughout North America was born with Tay-Sachs," says Prof. Robert Desnick of the Department of Human Genetics at New York's Mount Sinai Hospital. Prof. Desnick is in Israel as the guest of Jerusalem's Hadassah hospitals. He said yesterday that of the 10 babies born in North America in 2003 with Tay-Sachs, not a single one was Jewish.

Figures from Israel paint a similar picture. According to Prof. Joel Zlotogora, who heads the Health Ministry's Department of Community Genetics, just one baby was born with Tay-Sachs in Israel in 2003. Insofar as is known, not a single baby in Israel was born with Tay-Sachs last year, but as the disease takes some six months to manifest itself, the figures for 2004 are not final.
Desnick says that the data for the past two years may stem from a coincidental fluctuation in the incidence of the disease, and that isolated cases may appear this year or the next. He stresses, nevertheless, that whatever the case may be, the disease appears to have disappeared almost completely from among the Jewish nation.
How has this been accomplished? A simple answer: eugenics. A genetic test for the Tay-Sachs gene has been available for many years, able to determine conclusively whether a baby has the disease, and to warn adults that they carry the mutated gene. This permits the screening of couples planning to have children to determine if both carry the gene and thus risk having a child with Tay-Sachs.

Prof. Gideon Bach, who heads the Department of Genetics at Hadassah University Hospital, Ein Karem, says the eradication of Tay-Sachs can be attributed primarily to the fact that the general public in Israel is advised to carry out, at the expense of the state, genetic tests to diagnose the disease before the birth of the baby. In the event an unborn baby is diagnosed with Tay-Sachs, the pregnancy is usually terminated.
Another reason for the eradication of the disease, Bach says, is the work of the ultra-Orthodox association, Dor Yesharim. The association carries out tests on young individuals to check whether they are genetically "suitable." The results of these tests are passed on to the matchmaker. If there is a risk that a designated couple may give birth to children affected with Tay-Sachs, the matchmaker will report that the match is unsuitable.
Bach, who works with Dor Yesharim, says that numerous intended couples have been split up in the wake of genetic testing.
The American Heritage Dictionary defines eugenics as "the study of hereditary improvement of the human race by controlled selective breeding." Eugenics was a fairly popular subject in Europe and the US in the early 20th century. However, the monstrous crimes of Nazi Germany - including the systematic genocide of Jews and other "inferior" ethnic groups - justified by Hitler and his henchmen with psuedo-scientific nonsense dressed up in eugenic language so tarnished the concept that the word eugenics remains something of an epithet to this day. Opponents of the idea that behavior has a genetic basis used the Nazi fascination with eugenics to discredit the concept by equating it with Nazism, even though it had existed prior to the rise of Hitler and had been embraced by many of the nations and statesmen who fought and defeated Nazism. Oddly, central economic planning and state control of private property - also central ideas of the Nazi (National Socialist) state - were not disavowed by left-leaning Western intellectuals, though both concepts clearly made it possible for Hitler to perpetrate his crimes.

Despite the intellectuals' disaffection with genetics, mounting scientific evidence eventually turned the tide in favor of the genetic basis of human behavior. Eugenics has been slower to recover and is still viewed by many as a dangerous, or at least publiclly unmentionable, idea. And yet, eugenics - selective breeding - remains a simple idea whose effectiveness has been borne out by five thousand years of agriculture and animal husbandry. The fact that the Nazi misused a particular scientific idea doesn't vitiate its validity. Nazi scientist pioneered rocketry, and used the science to kill, but no one would call NASA (once led by "rehabilitated" Nazi Wernher von Braun) a Nazi program. In the case of Tay-Sachs, the effort to prevent carriers of the gene to marry and produce children has all but eliminated the birth of babies with Tay-Sachs amongst Jews. However those involved may choose to characterize their work, when they urge couples with the gene not to have children together, they are engaging in selective breeding - in other words, voluntary eugenics.

As noted in the article, some births of Tay-Sachs afflicted children continue amongst non-Jews, likely the result of intermarriage between Jews and non-Jews at some point in the non-Jewish parents' family tree. Since Tay-Sachs genes continue to circulate in a tiny percentage of the non-Jewish population (due to intermarriage), a small number of Tay-Sachs children will continue to be born to non-Jewish parents who would not expect to carry the mutated gene and thus never been counseled or tested.

Of course, the article cited above indicates only that efforts within Israel and the broader international Jewish community are directed at preventing the birth of Tay-Sachs afflicted babies. This will eliminate the expression of the gene (the disease itself) and prevent a great deal of unnecessary suffering, but it does not excise the mutated gene itself from the Jewish gene pool. For that to happen, all carriers of the gene would have to be counseled not to have children - or to terminate embryos or fetuses found to be carrying a single copy of the inactive gene, not just those with two inactive genes. That would eliminate the inactive gene, and thus the disease, permanently.

The lesson here is that, despite the hysterics that even its mere mention causes, eugenics can be used for good and becomes dangerous only when the government begins to use physical coercion to force people to participate in eugenic programs.


At 3:00 PM , Blogger Joe said...

The matchmaker part scares me a bit. People let their romantic lives be determined by this, as opposed to simply marrying whomever they love?


At 11:28 AM , Anonymous Anonymous said...

I believe there is a form of tay-sachs that is not ultimately fatal... it occurs around the ages 20-35. It does, however, mke you spend the rest of your days in a wheelchair. With mental retardation.

At 4:07 AM , Anonymous Anonymous said...

into animations sells projecting inducted brewster panorama spoiled teresadeca attrition emboli
servimundos melifermuly

At 1:19 PM , Anonymous Anonymous said...

great article. I would love to follow you on twitter.

At 6:48 PM , Anonymous propecia and hair loss said...

HI eugenics really can help the problem is that it don't eliminates at all the deadly disease so we need to work and really make that eugenics eliminated at all .

At 12:46 AM , Anonymous Anonymous said...

Nο mаttеr if some onе ѕеаrchеs for his requіrеd thing, thus he/shе wants to
be available that іn dеtaіl, thus that thing is maintainеd over here.

Alsο vіsit my homepagе ... MintedPoker Bonus


Post a Comment

Subscribe to Post Comments [Atom]

<< Home