Outcome of chromosomally abnormal pregnancies in Lebanon: obstetricians' roles during and after prenatal diagnosis.

OBJECTIVES: To better understand obstetrician experiences in Lebanon when disclosing abnormal amniocentesis results. METHODS: Structured interviews with 38 obstetricians identified as caregivers from the American University of Beirut Medical Center Cytogenetics Laboratory database of patients with abnormal amniocentesis results between 1999 and 2005. RESULTS: Obstetricians were primarily male, Christian, and with an average of 14 years of experience. They reported doing most pre-amniocentesis counseling, including discussion of risk for common autosomal aneuplodies (95%), and procedure-related risk (95%). Obstetricians reported that 80% of patients at risk for aneuploidy underwent amniocentesis. The study population reported on 143 abnormal test results (124 autosomal abnormalities). When disclosing results, obstetricians reportedly discussed primarily physical and cognitive features of the diagnosis. They varied in levels of directiveness and comfort in providing information. Our records showed that 59% of pregnancies with sex chromosome abnormalities were terminated compared to 90% of those with autosomal aneuploidies; various reasons were proposed by obstetricians. CONCLUSIONS: This study is among the few to assess prenatal diagnosis practices in the Middle East, with a focus on the role of the obstetrician. Given the influence of culture and social norms on prenatal decision-making, it remains important to understand the various impacts on clinical practice in many nations.

Analysis of PALB2/FANCN-associated breast cancer families.

No more than approximately 30% of hereditary breast cancer has been accounted for by mutations in known genes. Most of these genes, such as BRCA1, BRCA2, TP53, CHEK2, ATM, and FANCJ/BRIP1, function in DNA repair, raising the possibility that germ line mutations in other genes that contribute to this process also predispose to breast cancer. Given its close relationship with BRCA2, PALB2 was sequenced in affected probands from 68 BRCA1/BRCA2-negative breast cancer families of Ashkenazi Jewish, French Canadian, or mixed ethnic descent. The average BRCAPRO score was 0.58. A truncating mutation (229delT) was identified in one family with a strong history of breast cancer (seven breast cancers in three female mutation carriers). This mutation and its associated breast cancers were characterized with another recently reported but unstudied mutation (2521delA) that is also associated with a strong family history of breast cancer. There was no loss of heterozygosity in tumors with either mutation. Moreover, comparative genomic hybridization analysis showed major similarities to that of BRCA2 tumors but with some notable differences, especially loss of 18q, a change that was previously unknown in BRCA2 tumors and less common in sporadic breast cancer. This study supports recent observations that PALB2 mutations are present, albeit not frequently, in breast cancer families. The apparently high penetrance noted in this study suggests that at least some PALB2 mutations are associated with a substantially increased risk for the disease.