Health Scan: Bone density gene

Also, Jerusalem tests new osteoporosis drug; also, Third World children labor away making surgical instruments for the West.

By JUDY SIEGEL-ITZKOVICH
A defective gene that helps explain why its bearers lose bone density has been discovered by researchers at Ben-Gurion University of the Negev and Soroka University Medical Center in Beersheba. Prof. Eli Hershkovitz, Dr. Neta Leventhal and colleagues published their research in the American Journal of Human Genetics.
Studying rare, extreme forms of common disease lays the foundation for identifying the mechanisms that underlie the more common forms, they note. Studies in rare bone diseases with an inheritance pattern that can be attributed to a defect in a single gene have proven their potential for identifying several previously unknown genes that play key roles in regulating bone mass and bone turnover.
Their team studied a large Beduin family of married first cousins with cases of hypophosphatemic rickets (soft bones due to loss of phosphates). Further research by Prof. Ruti Parvari of the department of developmental genetics and virology and National Institute of Biotechnology in the Negev by master’s degree student Luba Avizov found on what chromosome the gene is located.  Dr. Varda Levi-Litan, a doctoral student, identified the mutation, and with the help of Prof. J. Goding from Australia the group further succeeded in demonstrating that the mutation causes loss of function of the gene. This result was surprising since previously described inactivating mutations in this gene were shown to cause generalized arterial calcifications that caused death in infancy, but the Beersheba researchers found no such problems in their Beduin patients.
Mineral loss in bone, which also leads to osteoporosis, affects nearly 45 million postmenopausal women (and a smaller number of men) worldwide. Bone mineral density has a strong genetic component.  Many genetic variants have a modest effect on mineral loss but interact with environmental factors such as diet and exercise. Although there has been extensive progress in identifying the genetic variants that regulate susceptibility to osteoporosis, most of these apparently have yet to be discovered. Bone contains about 85 percent of total body phosphate, but despite its broad biological importance, the mechanism is only partly understood. Only three genes have been identified as crucial for the internal equilibrium (homeostasis) of phosphate.
The identification of the new gene contributes to a better understanding of phosphate homeostasis and possible intervening in the pathological situations of reduced BMD and osteoporosis. Future research is needed to verify the contribution of natural-occurring changes in this gene.
JERUSALEM TESTS NEW OSTEOPOROSIS DRUG
Meanwhile, the osteoporosis center at Hadassah University Medical Center on Jerusalem’s Mount Scopus is looking for suitable candidates to participate in clinical trials of a new experimental oral drug for osteoporosis. The drug is based on the small molecule MK-5442, which inhibits calcium-sensing receptions on the thyroid gland and causes increased section of endogenous PTH, which mimicks the function of drugs such as Forteo. Experimentation with animals and Phase-1 tests (to show safety) on healthy women showed that the drug has a beneficial effect like Forteo, which has the disadvantage of having to be injected daily, is very expensive and can be given for a maximum of two years. The oral pill, given free to participants, does not have such disadvantages. In addition, most women with osteoporosis are not eligible to get Forteo from their health funds.
Prof. Joseph Foldes, head of the osteoporosis center, said he is looking for postmenopausal women aged 45 to 85 who have been taking Fosalan (or its generic forms, Alendronate and Maxibone) for at least three years. The clinical trial is a double-blind controlled study, with each participant having a four-out-of-six chance of getting the new drug and a one-out-of-six probability of either continuing with Fosalan or getting a harmless placebo. All three options, says Foldes, are valid in the clinical practice when patients seek advice about whether to continue long-term bisphosphonate treatment for osteoporosis. Thus, he says, there is no real placebo.
Potential candidates, who must commit themselves to visit the hospital nine times for tests, should call (02) 584-5100 or fax (02) 584-5050. 
HELP FOR PARENTS OF AUTISTIC CHILDREN
A private member’s bill that will entitle families of autistic children to get state-financed treatment by a social worker, psychologist or other paramedical professional has been passed by the Knesset. The law was initiated by MKs Rachel Adatto and Ze’ev Bielsky. Such children will get up to three hours of paramedical treatment a week and be able to choose a clinical communications specialist, physiotherapist or occupational therapist. Adatto, a gynecologist and lawyer by training, said the new law opens options for parents who have a difficult time raising children with disabilities.
SLAVING AWAY
It is now known that small children as well as adults in the ThirdWorld work almost like slaves making surgical instruments used in theWest. The British Medical Association recently issued a protest, andcalled on the National Health Service in Scotland to adopt new guidanceon ethical purchasing. Dr. Mahmood Bhutta, advisor on the BMA's medicalfair and ethical trade group, said: “There is evidence to suggest thatmany supplies used in the NHS are produced in unhealthy, unsafe andunfair working conditions. Workers in the developing world are poorlypaid and exposed to hazardous conditions. For example, many surgicalinstruments are made in Pakistan, where workers work 12 hours a day,seven days a week. Some suffer serious injuries due to poor standardsof health and safety. There is also a use of child labor, with someworkers as young as seven. It seems perverse that laborers around theworld are risking their lives to supply us with equipment to saveBritish lives.”