Origin and distribution of the BRCA2-8765delAG mutation in breast cancer. (25/103)

BACKGROUND: The BRCA2-8765delAG mutation was firstly described in breast cancer families from French-Canadian and Jewish-Yemenite populations; it was then reported as a founder mutation in Sardinian families. We evaluated both the prevalence of the BRCA2-8765delAG variant in Sardinia and the putative existence of a common ancestral origin through a haplotype analysis of breast cancer family members carrying such a mutation. METHODS: Eight polymorphic microsatellite markers (D13S1250, centromeric, to D13S267, telomeric) spanning the BRCA2 gene locus were used for the haplotype analysis. Screening for the 8765delAG mutation was performed by PCR-based amplification of BRCA2-exon 20, followed by automated sequencing. RESULTS: Among families with high recurrence of breast cancer (> or = 3 cases in first-degree relatives), those from North Sardinia shared the same haplotype whereas the families from French Canadian and Jewish-Yemenite populations presented distinct genetic assets at the BRCA2 locus. Screening for the BRCA2-8765delAG variant among unselected and consecutively-collected breast cancer patients originating from the entire Sardinia revealed that such a mutation is present in the northern part of the island only [9/648 (1.4%) among cases from North Sardinia versus 0/493 among cases from South Sardinia]. CONCLUSION: The BRCA2-8765delAG has an independent origin in geographically and ethnically distinct populations, acting as a founder mutation in North but not in South Sardinia. Since BRCA2-8765delAG occurs within a triplet repeat sequence of AGAGAG, our study further confirmed the existence of a mutational hot-spot at this genomic position (additional genetic factors within each single population might be involved in generating such a mutation).  (+info)

Qat habit in Yemen society: a causative factor for oral periodontal diseases. (26/103)

The effect of a common habit among Yemeni population on the periodontal status was investigated. This cross-sectional study was done on 2500 Yemenis with mean age 27.01 years (1818 males and 682 females). Among these 1528 were qat chewers and 972 were non-chewers. Detailed questionnaire and pre-designed scoring system for the periodontal status were employed for each case. Study results indicated that out of 972 non-chewers 116(12%) had periodontal pocketing and 18 (1.9%) cases had gingival recession. On the other hand, out of 1528 chewers, 468 (31.8%) had periodontal pockets and 98 (6.4%) with gum bleeding, p<0.05. These effects were found to increase with increased frequency and duration of chewing. It was concluded that habit of qat can cause damage to the periodontal ligament as pocketing and gum recession.  (+info)

Y-chromosome diversity characterizes the Gulf of Oman. (27/103)

Arabia has served as a strategic crossroads for human disseminations, providing a natural connection between the distant populations of China and India in the east to the western civilizations along the Mediterranean. To explore this region's critical role in the migratory episodes leaving Africa to Eurasia and back, high-resolution Y-chromosome analysis of males from the United Arab Emirates (164), Qatar (72) and Yemen (62) was performed. The role of the Levant in the Neolithic dispersal of the E3b1-M35 sublineages is supported by the data, and the distribution and STR-based analyses of J1-M267 representatives points to their spread from the north, most likely during the Neolithic. With the exception of Yemen, southern Arabia, South Iran and South Pakistan display high diversity in their Y-haplogroup substructure possibly a result of gene flow along the coastal crescent-shaped corridor of the Gulf of Oman facilitating human dispersals. Elevated rates of consanguinity may have had an impact in Yemen and Qatar, which experience significant heterozygote deficiencies at various hypervariable autosomal STR loci.  (+info)

CADASIL in Arabs: clinical and genetic findings. (28/103)

BACKGROUND: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is increasingly recognized as an inherited arterial disease leading to a step-wise decline and eventually to dementia. CADASIL is caused by mutations in NOTCH3 epidermal growth factor-like repeat that maps to chromosome 19. CADASIL cases have been identified in most countries of Western and Central Europe, the Americas, Japan, Australia, the Caribbean, South America, Tanzania, Turkey, South Africa and Southeast Asia, but not in Arabs. METHODS: We studied three families from Saudi Arabia (Family A), Kuwait (Family B) and Yemen (Family C) with 19 individuals affected by CADASIL. RESULTS: The mean age of onset was 31 +/- 6 and the clinical presentation included stroke in 68%, subcortical dementia in 17% and asymptomatic leukoariosis detected by MRI in 15%. Migraine and depression were frequently associated, 38% and 68% respectively. The mean age of death was 56 +/- 11. All NOTCH3 exons were screened for mutations, which revealed the presence of previously reported mutations c.406C>T (p.Arg110>Cys) in two families (family A&B) and c.475C>T (p.Arg133>Cys) mutation in family C. CONCLUSION: CADASIL occurs in Arabs, with clinical phenotype and genotype similar to that in other ethnic groups.  (+info)

A common founder mutation of CERKL underlies autosomal recessive retinal degeneration with early macular involvement among Yemenite Jews. (29/103)

PURPOSE: To investigate the genetic basis and clinical manifestations of a characteristic form of retinal degeneration in the Yemenite Jewish population. METHODS: Haplotype analysis for all known genes and loci underlying autosomal recessive nonsyndromic retinal degeneration was performed in a Yemenite Jewish family segregating autosomal recessive severe retinal degeneration. The causative mutation was detected by direct sequencing of the underlying gene, and its prevalence in additional affected and unaffected Yemenite Jews was determined. Patients who were homozygous for this mutation underwent ophthalmic evaluation, including funduscopy, electroretinography, electro-oculography, perimetry, and color vision testing. RESULTS: In the studied Yemenite Jewish family, we found evidence for linkage to the CERKL gene. Direct sequencing revealed a novel homozygous splice-site mutation, c.238+1G>A. An in vitro splicing assay demonstrated that this mutation leads to incorrect splicing. c.238+1G>A was found to cause retinal degeneration in six additional Yemenite Jewish families. The carrier frequency of this mutation in the Yemenite Jewish population is 4.4%. All c.238+1G>A homozygotes manifest widespread progressive impairment of rod and cone function with early macular involvement. CONCLUSIONS: c.238+1G>A is the second reported mutation of CERKL and is a prevalent founder mutation that underlies approximately 33% of autosomal recessive retinal degeneration cases in the Yemenite Jewish population. It is associated with a characteristic retinal degeneration phenotype with early macular involvement, concomitant progression of rod and cone impairment, and characteristic fundus findings. The identification of this mutation and phenotype will facilitate molecular diagnosis, carrier screening, and genetic counseling in the Yemenite Jewish population.  (+info)

Laparoscopic cholecystectomy can be safely performed in a resource-limited setting: the first 49 laparoscopic cholecystectomies in Yemen. (30/103)

BACKGROUND: Laparoscopic cholecystectomy (LC) is the gold standard for gallstone disease. Many studies have confirmed the safety and feasibility of LC and have shown that it is comparable regarding complications to open cholecystectomy (OC). The aim of this study was to evaluate the outcomes of LC including safety, feasibility in a resource-poor setting like Yemen, and also to compare the outcomes of LC with those of OC. METHODS: This was a prospective, nonrandomized, comparative study of 112 patients who were admitted to Alburaihy Hospital with a diagnosis of gallstone disease and underwent cholecystectomy from July 1998 to March 2004. Hospital stay, duration of operation, postoperative analgesia, and morbidity due to wound infection, bile leak, common bile duct (CBD) injury, missed CBD stone, bleeding, subphrenic abscess, and hernia were evaluated. Patients were followed up on an outpatient basis. RESULTS: Forty-nine patients underwent LC and 63 patients underwent OC. The mean age of LC patients was 43.96 years and of OC patients was 44.63 years. The 2 groups were similar in terms of age (p=0.740) and sex (p=0.535). No significant difference was found in the incidence of acute cholecystitis between the 2 groups (p=0.000). The mean operative duration for LC was 39.88 minutes versus 56.76 minutes for OC (p=0.000), and the mean hospital stay was 1.63 and 5.38 days for LC and OC, respectively (p=0.000). A drain was used frequently in OC (p=0.000). LC patients needed less analgesia (p=0.000). The morbidity rate in LC was 12.2% versus 6.3% for OC, which was not statistically significant (p=0.394), (p>0.05). Wound infection and bile leak were more common with LC. No mortalities were reported in either group. CONCLUSION: An experienced surgeon can perform LC safely and successfully in a resource-limited setting. As in other studies, LC outcomes were better than OC outcomes.  (+info)

Who develops severe malaria? Impact of access to healthcare, socio-economic and environmental factors on children in Yemen: a case-control study. (31/103)

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First dinosaur tracks from the Arabian Peninsula. (32/103)

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