Single-cell genetic analysis validates cytopathological identification of circulating cancer cells in patients with clear cell renal cell carcinoma.

Context: Circulating Rare Cells (CRC) are non-haematological cells circulating in blood. They include Circulating Cancer Cells (CCC) and cells with uncertain malignant features (CRC-UMF) according to cytomorphology. Clear cell renal cell carcinomas frequently bear a mutated Von Hippel-Lindau (VHL) gene.

Genetics and genomic medicine in Tunisia.

Genetics and genomic medicine in Tunisia. [Image: see text]

Family history predictors of BRCA1/BRCA2 mutation status among Tunisian breast/ovarian cancer families.

Background: With the increasing request for BRCA1/BRCA2 mutation tests, several risk models have been developed to predict the presence of mutation in these genes; in this study, we have developed an efficient BRCA genetic testing strategy.

Method: As first step, to identify predictor variables associated with BRCA status, we have undertaken a cumulative mutation analysis including data from three Tunisian studies. Then, we have developed a logistic regression model for predicting the likelihood of harboring a BRCA mutation.

Estimating the Total Pathogenic Allele Frequency of Autosomal Recessive Disorders in Case of Consanguinity.

Objective: Estimating the total allele frequency of all pathogenic alleles of an autosomal recessive disease is not possible if only mutational data of a sample of affected individuals are available. However, if the affected individuals come from a population where consanguinity is not uncommon, this total allele frequency can be estimated by additionally using the positive individual inbreeding coefficients or an estimate of the population inbreeding coefficient. In this paper, we propose two estimators.

The relationship between telomere length and clinicopathologic characteristics in colorectal cancers among Tunisian patients.

Alterations in telomere dynamics have emerged as having a causative role in carcinogenesis. Both the telomere attrition contribute to tumor initiation via increasing chromosomal instability and that the telomere elongation induces cell immortalization and leads to tumor progression. The objectives of this study are to investigate the dynamics of telomere length in colorectal cancer (CRC) and the clinicopathological parameters implicated.

CONSANGUINITY AND HOMOZYGOSITY AMONG TUNISIAN PATIENTS WITH AN AUTOSOMAL RECESSIVE DISORDER.

Consanguineous unions are a deeply rooted social practice among traditional societies. Despite their presumed social advantages, they can result in several health conditions. The aim of this study was: i) to compare consanguinity levels between Tunisian patients affected with autosomal recessive disorders (ARDs) and those with a chromosomal abnormality; and ii) to gain more insight into the mutational status of patients affected with ARDs.

RGS6: a novel gene associated with congenital cataract, mental retardation, and microcephaly in a Tunisian family.

Purpose: The object of this study is to identify the underlying genetic defect in a consanguineous Tunisian family affected with autosomal recessive congenital cataract associated with mental retardation and microcephaly.

Methods: A whole-genome scan was performed with polymorphic microsatellites in the axiom data for the screened members. Homozygous regions were analyzed with integrated Systems Tool for Eye gene Discovery (iSyTE), to identify candidate genes with lens-enriched expression that were potentially associated with cataract.

High-resolution melting (HRM) assay for the detection of recurrent BRCA1/BRCA2 germline mutations in Tunisian breast/ovarian cancer families.

Germline deleterious mutations in the BRCA1/BRCA2 genes are associated with an increased risk for the development of breast and ovarian cancer. Given the large size of these genes the detection of such mutations represents a considerable technical challenge. Therefore, the development of cost-effective and rapid methods to identify these mutations became a necessity.

Diagnostic exome sequencing to elucidate the genetic basis of likely recessive disorders in consanguineous families.

Rare, atypical, and undiagnosed autosomal-recessive disorders frequently occur in the offspring of consanguineous couples. Current routine diagnostic genetic tests fail to establish a diagnosis in many cases. We employed exome sequencing to identify the underlying molecular defects in patients with unresolved but putatively autosomal-recessive disorders in consanguineous families and postulated that the pathogenic variants would reside within homozygous regions.

Molecular analysis of the PAX6 gene for aniridia and congenital cataracts in Tunisian families.

The aim of this study was to identify the genetic defect that is responsible for aniridia and congenital cataracts in two Tunisian families. Sequencing of the PAX6 gene in family F1 detected a novel c.265C>T transition in exon 6.

Prevalence of Bardet-Biedl syndrome in Tunisia.

Bardet-Biedl syndrome (BBS, OMIM 209900) is a ciliopathy causing multivisceral abnormalities. This disease is mainly characterized by obesity, post-axial polydactyly, hypogenitalism, intellectual disabilities, pigmentary retinopathy, and renal deficiency. The prevalence of BBS has been estimated in different populations, ranging from 1 in 160,000 in European populations to 1 in 13,000 in Bedouins from Kuwait.

The first missense mutation of NHS gene in a Tunisian family with clinical features of NHS syndrome including cardiac anomaly.

Nance-Horan Syndrome (NHS) or X-linked cataract-dental syndrome is a disease of unknown gene action mechanism, characterized by congenital cataract, dental anomalies, dysmorphic features and, in some cases, mental retardation. We performed linkage analysis in a Tunisian family with NHS in which affected males and obligate carrier female share a common haplotype in the Xp22.32-p11.

Non-syndromic autosomal recessive mental retardation in Tunisian families : exclusion of GRIK2 and TUSC3 genes.

Background: Mental retardation is one of the most frequent major handicap, with a 1-3 % frequency in the general population, it appear a major problem of public health. The recent progress of molecular biology and cytogenetic allowed to identify new genes for non syndromic autosomal recessive mental retardation (NSAR-MR).

Aim: Genetic analysis of NSAR-MR: the GRIK2 gene (6q16.

[Linkage analysis of six Algerian families with autosomal recessive non specific mental retardation].

Background: Mental retardation is one of the most frequent major handicap, with a 1-3 % frequency in the general population. The recent progress of molecular biology and cytogenetic allowed to identify new genes for non syndromic autosomal recessive mental retardation.

Aim: To seek a genetic linkage to the loci implied in the nonspecific mental retardation transmitted into autosomal recessive (ARNSMR) in Algerian families with several affected members and to make the Genetic analysis of ARNSMR for 4 known loci: 3p25-pter; 4q24- q25, 19p13.

Absence of PITX3 mutation in a Tunisian family with congenital cataract and mental retardation.

Purpose: The PITX3 (pituitary homeobox 3) gene encodes for a homeobox bicoid-like transcription factor. When one allele is mutated, it leads to dominant cataract and anterior segment mesenchymal dysgenesis in humans. When both copies are mutated, homozygous mutation contributes to microphtalmia with brain malformations.

Tunisia: communities and community genetics.

The population of Tunisia rose from 2.7 millions before the Second World War to 10,074,951 in 2005. Modern Tunisians are the descendents of indigenous Berbers and of people from various civilizations that were assimilated into the population over the centuries.