Israel Medical Association Journal

Background: The Bloom syndrome gene, BLM, was mapped to 15q26.1 and its product was found to encode a RecQ DNA helicase. The Fanconi anemia complementation group C gene was mapped to chromosome 9q22.3, but its product function is not sufficiently clear. Both are recessive disorders associated with an elevated predisposition to cancer due to genomic instability. A single predominant mutation of each disorder was reported in Ashkenazi Jews: 2281delATCTGAinsTAGATTC for Bloom syndrome (BLM-ASH) and IVS4+4A®T for Fanconi anemia complementation group C.

Objectives: To provide additional verification of the mutation rate of BLM and FACC[1] in unselected Ashkenazi and non-Ashkenazi populations analyzed at the Sheba Medical Center, and to trace the origin of each mutation.

Methods: We used polymerase chain reaction to identify mutations of the relevant genomic fragments, restriction analysis and gel electrophoresis. We then applied the Pronto^TM kit to verify the results in 244 samples and there was an excellent match.

Results: A heterozygote frequency of 1:111 for BLM-ASH and 1:92 for FACC was detected in more than 4,000 participants, none of whom reported a family history of the disorders. The Pronto^TM kit confirmed all heterozygotes. Neither of the mutations was detected in 950 anonymous non-Ashkenazi Jews. The distribution pattern of parental origin differed significantly between the two carrier groups, as well as between each one and the general population.

Conclusions: These findings as well as the absence of the mutations in non-Ashkenazi Jews suggest that: a) the mutations originated in the Israelite population that was exiled from Palestine by the Roman Empire in 70 AD and settled in Europe (Ashkenazi), in contrast to those who remained; and b) the difference in origin distribution of the BS[2] and FACC mutations can be explained by either a secondary migration of a subgroup with a subsequent genetic drift, or a separate geographic region of introduction for each mutation.

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[1] FACC = Fanconi anemia complementation group C

Background: Classic Kaposi's sarcoma is a rare tumor with an indolent behavior. Local therapy is not applicable in disseminated cutaneous disease. Patients with advanced disease are usually treated with systemic chemotherapy.

Objectives: To assess the effectiveness and toxicity of  single-agent vinblastine in the treatment of disseminated and recurrent Kaposi's sarcoma.

Methods: Ten patients with wide cutaneous spread of classic Kaposis sarcoma were treated with single-agent vinblastine, 6 mg/m² intravenously once every 2 weeks. Vinblastine was continued for 2 months after achieving a maximal response.

Results: The male:female ratio was 2.3:1, and median age 64 years (range 50-79 years). The median number of involved nodules in the skin was 34. The overall response rate was 90%, 5 with complete response (50%) and 4 with partial response (40%). Complete responders had a longer duration of response than partial responders: 41.2 vs. 14.8 months. The median survival of all patients was 33 months. Side effects were minimal and tolerable.

Conclusions: Vinblastine is very effective in the treatment of extensive classic Kaposi's sarcoma, and results in a high response rate, long survival and disease-free survival with tolerable toxicity.

Background: Obesity, a common condition in developed countries, is recognized as a threat to health.

Objectives: To describe the distribution of weight in pregnant women and evaluate the influence of obesity on pregnancy outcome in a high parity northern Israeli population.

Methods: The study included 887 women who gave birth in the Western Galilee Medical Center during the period August to November 1995. The patients were classified as underweight, normal weight, overweight, or obese according to body mass index. Maternal demographic, obstetric, and perinatal variables were compared. A control group of 167 normal weight women were matched with the obese group for maternal age, parity, and gestational age.

Results: Obese mothers had a higher incidence of gestational diabetes and pregnancy-induced hypertension compared to normal weight mothers (5.4% vs. 1.8%, and 7.2% vs. 0.6% respectively, P<0.01), a higher rate of labor induction (20.4% vs. 10.2%, P<0.01), and a higher cesarean section rate (19.6% vs.10.8%, P<0.05). There was also a significant difference in the prevalence of macrosomia in the offspring (16.8% vs. 8.4%, P<0.05).

Conclusion: Obese pregnant women are at high risk for complications during delivery and therefore need careful pre-conception and prenatal counseling, as well as perinatal management.