Clinical and Genetic Features of Patients With Fanconi Anemia in Lebanon and Report on Novel Mutations in the FANCA and FANCG Genes.

Fanconi anemia (FA) is the most common inherited bone marrow failure syndrome and presents with cytopenias, characteristic physical features, increased chromosomal breaks, and a higher risk of malignancy. Genetic features of this disease vary among different ethnic groups. We aimed to identify the incidence, outcome, overall condition, and genetic features of patients affected with FA in Lebanon to optimize management, identify the most common genes, describe new mutations, and offer prenatal diagnosis and counseling to the affected families.

Functional classification of ATM variants in ataxia-telangiectasia patients.

Ataxia-telangiectasia (A-T) is a recessive disorder caused by biallelic pathogenic variants of ataxia-telangiectasia mutated (ATM). This disease is characterized by progressive ataxia, telangiectasia, immune deficiency, predisposition to malignancies, and radiosensitivity. However, hypomorphic variants may be discovered associated with very atypical phenotypes, raising the importance of evaluating their pathogenic effects.

Three new cases of ataxia-telangiectasia-like disorder: No impairment of the ATM pathway, but S-phase checkpoint defect.

Ataxia-telangiectasia-like disorder (ATLD) is a rare genomic instability syndrome caused by biallelic variants of MRE11 (meiotic recombination 11) characterized by progressive cerebellar ataxia and typical karyotype abnormalities. These symptoms are common to those of ataxia-telangiectasia, which is consistent with the key role of MRE11 in ataxia-telangiectasia mutated (ATM) activation after DNA double-strand breaks. Three unrelated French patients were referred with ataxia.

[An adult patient with 49, XXXXY syndrome: further clinical and biological delineation].

49, XXXXY syndrome is a rare sex chromosome aneuploidy occurring in 1:80 000-1:100 000 male births. Data on this aneuploidy in adulthood are limited, with most of the literature data based on paediatric patients. We report a new male patient whose 49, XXXXY diagnosis was formally made at the age of 54 years.