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Dravet syndrome (DS), previously known as severe myoclonic epilepsy of infancy, is a severe epileptic syndrome affecting children, with an incidence of 1/22,000 to 1/49,900 live births annually. Characterized by resistant and prolonged seizures, it often leads to intellectual impairment, with males being twice as susceptible as females. Its clinical features include recurrent seizures triggered by fever initially, but later occurring spontaneously, developmental delays, behavioral issues, and movement disorders. Sodium voltage-gated channel alpha subunit 1 (SCN1A) mutations, observed in about 90% of cases, are usually de novo, while mutations in other genes, such as protocadherin 19 (PCDH19), gamma-aminobutyric acid type A receptor subunit gamma 2 (GABRG2), and sodium voltage-gated channel alpha subunit 2 (SCN2A), can also contribute to the condition. Next-generation sequencing aids in identifying these genetic abnormalities. First-line treatments include anticonvulsant drugs such as valproate, clobazam, stiripentol, topiramate, and bromide. Second-line treatments for drug-resistant DS include stiripentol, fenfluramine, and cannabidiol. This literature review provides a comprehensive update on the genetic underpinnings of DS, highlighting SCN1A's predominant role and the emerging significance of other genes. Moreover, it emphasizes novel therapeutic approaches for drug-resistant forms, showcasing the efficacy of newer drugs such as stiripentol, fenfluramine, and cannabidiol. This synthesis contributes to our understanding of the genetic landscape of DS and informs clinicians about evolving treatment strategies for enhanced patient care. [ABSTRACT FROM AUTHOR]

Dravet syndrome is a severe form of epilepsy characterised by recurrent seizures and cognitive impairment. It is mainly caused by variant in the SCN1A gene in 90% of cases, which codes for the α subunit of the voltage-gated sodium channel. In this study, we present one suspected case of Dravet syndrome in Moroccan child that underwent exome analysis and were confirmed by Sanger sequencing. The variant was identified in the SCN1A gene, and is a new variant that has never been described in the literature. The variant was found de nova in our case, indicating that it was not inherited from the parents. The variant, SCN1A c.965-2A>G p.(?), is located at the splice site and results in an unknown modification of the protein. This variant is considered pathogenic on the basis of previous studies. These results contribute to our knowledge of the SCN1A gene mutations associated with Dravet syndrome and underline the importance of genetic analysis in the diagnosis and confirmation of this disorder. Further studies are needed to better understand the functional consequences of this variant and its implications for therapeutic strategies in Dravet syndrome. [ABSTRACT FROM AUTHOR]

Abstract: A sample of 267 unrelated Moroccan males from different ethnic groups (Arabs, Berbers and Sahrawi), was typed for 17 Y-STR loci (DYS19, DYS385, DYS389 I, DYS389 II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438, DYS439, DYS448, DYS456, DYS458, DYS635, Y GATA H4). Discrimination capacity (96.3%) and haplotype diversity (99.91%) were calculated. A total of 257 haplotypes were identified, of which 237 were unique and 10 were found in two individuals each. DYS385 showed the highest diversity (0.887) followed by DYS458 (0.820) as a single locus marker. [Copyright &y& Elsevier]

Lynch syndrome or hereditary nonpolyposis colorectal cancer (HNPCC) is the most common form of hereditary colorectal cancers. It increases cancer susceptibility, the risk of colorectal cancer in first-degree, endometrial cancer in women, and to a lesser extent, other cancers (ovarian, small bowel, stomach, urinary tract and hepatobiliary). Thus, the cumulative risk of developing colorectal cancer or endometrial cancer at the age of 80 years rises to 20 and 40% respectively. These cancers are characterized by a positive family history, their occurrence at an early age, and by the development of metachronous cancers in the same individual. This syndrome is transmitted in an autosomal dominant manner. The genes whose alteration is associated with the presence of an HNPCC belong to the family of DNA mismatch repair genes (DNA mismatch repair or MMR): MSH2, MLH1, and MSH6 are involved, in decreasing order of frequency, in 35%, 25% and 2% of cases respectively. Colonoscopic and gynecological monitoring is recommended for patients with a constitutional mutation in MSH2, MLH1 or Msh6 genes. We report one of the first moroccan case with Lynch syndrome whose constitutional mutation in the MLH1 gene was identified in a family member with colon cancer. In reply to the inquiry ofother healthy family members, a presymptomatic diagnosis was made allowing to formulate an appropriate monitoring strategy. Our study aims to highlight the role of oncogenetics in the management of patients with cancer and their families.