Background Multiple myeloma (MM) is a disease characterized by heterogeneous clinical presentations as well as complex genetic and molecular abnormalities. In MM, cytogenetic analysis is a challenge because of the low proliferation of malignant plasma cells. Thus, interphase fluorescence in situ hybridization (FISH), performed on sorted plasma cells detected abnormalities independently of a proliferative and infiltrative index. The purpose of this study was to explore, for the first time, the cytogenetic and molecular genetics features in Moroccan patients with multiple myeloma referred exclusively to National Reference Laboratory and to determine their risk stratification based on these features. Methods We performed cytogenetic analysis on 93 MM cases, all patients were subjected to FISH analysis, among which 45 patients have benefited from both FISH analysis and standard karyotype. Results Karyotype was normal in 78% (35/45) while, it was complex with varied structural and numerical abnormalities in 22% (10/45) of all patients, among which Hyperdiploid karyotype was found in 9% (n = 4 cases) and nonhyperdiploid in 13% (n = 6 cases). The most common numerical abnormalities were gains of chromosomes 3, 5, 9, 15, and 19. Whole chromosome losses were also frequent, affecting chromosomes X, 3, 14, 16 and 22. FISH analysis detected abnormalities in 50% of cases. The translocation t(4;14) and dup (1q) were the most frequent types of anomalies (14% and 13% respectively), followed by (17p) deletion and 14q32/IGH translocations with an undetermined origin (12% each) then the (1p) deletion (4%). For the normal karyotypes, FISH revealed chromosome abnormalities in 46%. Conclusion This study compares the results of cytogenetic analysis of chromosomal abnormalities in the Moroccan population with other countries. ½ patient showed at least one type of molecular genetic abnormalities. Therefore, the introducing of the cytogenetic analysis is obligatory in the diagnosis of multiple myeloma.

Myoclonus–dystonia (M‐D) is a pleiotropic neuropsychiatric disorder with autosomal dominant mode of inheritance with variable severity and incomplete penetrance. Pathogenic variants in ξ‐sarcoglycan gene SGCE are the most frequently known genetic cause of M‐D with maternal imprinting, and in most cases, a symptomatic individual inherits the pathogenic variant from his or her father. This work reported a missense mutation c.662G> T inherited in the M‐D Moroccan family described for the first time, which is deleterious based on protein modeling analysis.

Multiple myeloma (MM) is a hematological malignancy in which monoclonal plasma cells multiply in the bone marrow and monoclonal immunoglobulins are overproduced in older people. Several molecular and cytogenetic advances allow scientists to identify several genetic and chromosomal abnormalities that cause the disease. The comprehension of the pathophysiology of MM requires an understanding of the characteristics of malignant clones and the changes in the bone marrow microenvironment. This study aims to identify the central genes and to determine the key signaling pathways in MM by in silico approaches. A list of 114 differentially expressed genes (DEGs) is important in the prognosis of MM. The DEGs are collected from scientific publications and databases ( https://www.ncbi.nlm.nih.gov/ ). These data are analyzed by Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) software ( https://string-db.org/ ) through the construction of protein-protein interaction (PPI) networks and enrichment analysis of the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, by CytoHubba, AutoAnnotate, Bingo Apps plugins in Cytoscape software ( https://cytoscape.org/ ) and by DAVID database ( https://david.ncifcrf.gov/ ). The analysis of the results shows that there are 7 core genes, including TP53; MYC; CDND1; IL6; UBA52; EZH2, and MDM2. These top genes appear to play a role in the promotion and progression of MM. According to functional enrichment analysis, these genes are mainly involved in the following signaling pathways: Epstein-Barr virus infection, microRNA pathway, PI3K-Akt signaling pathway, and p53 signaling pathway. Several crucial genes, including TP53, MYC, CDND1, IL6, UBA52, EZH2, and MDM2, are significantly correlated with MM, which may exert their role in the onset and evolution of MM.

Cytogenetic and iFISH plays a major part in the diagnosis of the MM and have an important prognostic significance. 10–15% of patients with amyloidosis will also have multiple myeloma (MM). Few studies have addressed the clinical and cytogenetic features of patients with AL amyloidosis with concurrent multiple myeloma. This study of MM case in which we found a near tetraploid complex karyotype with the t(11;14) (q13;q32) abnormality in cytogenetic analysis and the presence of t(4;14) and del(17p) by iFISH, referred to several studies which showed the translocation t(11;14) as the most frequent abnormality in both AL amyloidosis and MM.

Les marqueurs chromosomiques peuvent être définis comme des petits chromosomes de structure anormale présents en addition aux 46 chromosomes humains connus. C'est un groupe hétérogène d'anomalies de structure chromosomique pouvant être avec ou sans conséquence phénotypique. Plusieurs tentatives sont réalisées afin de retrouver une corrélation génotype-phénotype lors de la présence d'un marqueur chromosomique. L'identification du marqueur, son origine et sa structure suit une stratégie bien codifiée actuellement allant d'abord de l'orientation clinique suivie des techniques de cytogénétique conventionnelle (caryotype métaphasique standard, bandes C, NOR) et de cytogénétique moléculaire (M-FISH, CGH, CGH array) puis une détection par des techniques plus ciblées (painting, sondes locus spécifique). Cet ensemble permet une meilleure analyse et correspondance clinico-génétique. Nous rapportons le cas d'un nourrisson présentant une dysmorphie faciale avec un retard psychomoteur dont l'analyse cytogénétique a révélé la présence d'un marqueur chromosomique avec un caryotype métaphasique 47,XX,+mar. A travers cette observation, nous mettons en valeur le rôle de la cytogénétique conventionnelle et moléculaire dans le diagnostic des syndromes dysmorphiques permettant une meilleure prise en charge du patient et un conseil génétique adéquat pour sa famille

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L'anémie de Fanconi est une maladie récessive associée à une instabilité chromosomique, elle est marquée par une hétérogénéité phénotypique qui inclut une insuffisance médullaire, un syndrome malformatif variable, une prédisposition à développer des leucémies aiguës myéloïdes (LAM) et une hypersensibilité cellulaire aux agents pontant l'ADN. Le diagnostic est basé sur l'augmentation anormale du taux de cassures chromosomiques spontanées mais surtout, et de manière spécifique, sur une augmentation nette de ces cassures chromosomiques en présence d'agents alkylants bifonctionnels, ce qui est le cas pour nos six patients. Le conseil génétique rejoint celui des maladies autosomiques récessives. Nous rapportons nos premières observations au CHU Hassan II Fès, confirmées par la mise en évidence d'une grande instabilité chromosomique après culture sous Mitomycine C en comparaison avec un témoin normal. Le but de cet article est la mise à jour de nos connaissances sur la génétique de l'Anémie de Fanconi et à travers ces six observations nous illustrons le rôle de la cytogénétique dans le diagnostic et le conseil génétique pour une meilleure prise en charge aussi bien des enfants atteints que de leurs familles.

Cup Like acute myeloid leukemia is the rarest form of children leukemia. We present a case of Cup Like Acute Myeloid Leukemia (AML) with t(4;12) (q12;p13) associated with two other clones t(1;16)(q12;q24) and t(12;13)(p13;q13). Cytogenetic and iFISH are highly relevant for the prognosis of and therapeutic decisions in LAM.