Haifa scientists’ find may help millions

New DNA data could save people of African ancestry from failing kidneys.

By JUDY SIEGEL-ITZKOVICH
DNA 311 (photo credit: )
DNA 311
(photo credit: )
Fortymillion Americans have chronic (delete end-stage) kidney disease. About500,000 of them have end-stage kidney disease (ESKD), as DO 5,000Israelis. African- and Hispanic Americans have a double-to-quadruplerisk for the fatal disorder, compared to Caucasians of European origin.
Nowan Israeli research team has discovered new genetic data on a DNAregion that could predict who will develop the disease, and eventuallyhelp millions of people of African ancestry, The Jerusalem Post has learned.
So far, the only ways to prolong their lives are undergoing dialysis a few times a week or getting a kidney transplant.
Theteam, headed by Prof. Karl Skorecki – a nephrologist (kidney expert) atthe Technion-Israel Institute of Technology’s Rappaport Medical Facultyand director of medical and research development at Haifa’s RambamMedical Center – has just published a paper on the subject in theonline edition of the prestigious journal Human Molecular Genetics; it will appear in the print edition in a few weeks.
Theteam’s findings so far, said Skorecki, can already advance the use ofearly genetic screening for people at high risk for the disorder so itcan be prevented. Future comparative genetic research could helpidentify the specific mutation responsible for ESKD and provide abetter understanding of what mechanism causes irreversible damage tothe kidneys’ glomeruli (which filter out the toxins from the blood) –even leading to new medical treatments.
Skorecki, anautodidactic genetic researcher, became known worldwide over a decadeago when he showed that Jewish men who had been told by their fathersthat they were of the priestly tribe shared the same type array of sixchromosomal markers in their Y chromosomes. These patrilineal markerswere found in both Sephardi and Ashkenazi kohanim, pointing to a commonpriestly tribe population origin before the Diaspora during the RomanEmpire.
A year ago, two US research groups identified onChromosome 22 a gene called MYH9, which has mutations that explain thehigh prevalence of ESKD among African-Americans (1,010 per million,compared with 520 per million among Hispanics and only 279 per millionamong whites of European origin).
The Skorecki team – whichincluded Dr. Doron Behar and colleagues from Rambam, Tel AvivUniversity, Hadassah-University Medical Center in Jerusalem’s Ein Keremand the US National Institutes of Health – went further and discoveredimportant new genetic data that explained the high prevalence of thekidney disease among people of African origin. They also realized thatHispanic Americans, who have a combination of Central African, Europeanand Native American ancestry, are therefore also at higher risk, butnot as high as African-Americans, who have mostly genes of CentralAfrican origin. About 30 percent of the global genetic ancestry amongHispanic Americans could be attributed to the African geneticcomponent, they wrote.
Skorecki told the Post onThursday that his team had previously found that Ethiopian Jews did notshare the higher risk for the disease, thus hinting that they might nothave the Central African DNA makeup that predisposes people to ESKD.The team is now testing this in Ethiopia and Israel.
As previousresearchers had found no influence of socioeconomic conditions incausing ESKD to break out, the Skorecki team decided to look at geneticfactors. They examined the genomes of 1,425 African- and Hispanic(Puerto Rican, Dominican and other) American adults treated in dialysisand ambulatory clinics in New York City and compared them with acontrol group of mostly healthy but elderly black and HispanicAmericans living in nursing homes, who were past the age of developingESKD. These people were descendants of the 12 million African slavesbrought to North America hundreds of years ago.
Skorecki told the Postthat he had been in touch with representatives of the Negev’snon-Jewish community of Black Hebrews, who came here decades ago fromthe US. The Black Hebrews – whose ancestry is 85% African and the restEuropean – will come to see him in Haifa so he can check whether theyalso have the African risk variants. They claim to be healthy and notto suffer from a significant amount of kidney disease.