Y chromosome microdeletions in infertile Moroccan males: 10 years laboratory experience in AZF deletions

Genetic causes of male infertility are abnormalities in chromosome numbers and/or structures, Y-chromosome deletions and gene mutations. Genetic screening of male infertility is rarely done in our country. The purpose of the study was to investigate the frequencies and types of Y chromosome microdeletions in infertile men, based on studies done in the Human Genetics Laboratory of the Pasteur Institute in Morocco.A total of 543 infertile men were screened for Y chromosome microdeletions.The prevalence of AZF Y-chromosome microdeletions among infertile men range from 3% to 10% depending on patients selected. The most frequent microdeletions were detected in the AZFc region, followed by AZFbc, AZFb, AZFa, AZFab.These results indicate the need for Y chromosome microdeletion screening for better management of infertile patients.We hope to encourage use of genetic diagnosis and also research in this field to initiate collaboration for clinical management and appropriate genetic diagnosis and counselling for male infertility

Genetic study of sex inversion in humans

Sex reversal is considered to be a form of disorders of sex development or DSD (disorders/Differences of sex development). This is an inconsistency between gonadal, phenotypic and chromosomal sex. Sexual development, including the development of gonads and organs reproduction and the acquisition of secondary sexual characteristics, is under genetic control. Indeed, following the bibliographic study carried out in this report, we were able to better understand the pathophysiology of sex reversal, enumerate the associated genetic mutations and identify the signaling pathways affected. In addition, a retrospective study was performed to determine the frequency of sex reversal compared to other categories of DSD. This work focused on a sample of 981 patients with clinical signs indicating the presence of DSD. These patients presented to the Cytogenetics laboratory of the Institut Pasteur in Morocco between the years 2011 and 2021. The karyotype was performed on a heparinized tube according to the standard method. Based on the karyotype results, we found 74 cases of sex inversion corresponding to 7.54%. Abnormal karyotypes accounted for 37.31% with a predominance of Turner syndrome (41.53%), 26.23% of Klinefelter syndrome, 12.3% of patients presented with XY female type sex inversion, 7.92% with sex reversal type XX men and 7.65% had mixed gonadal dysgenesis. Finally, to guide the diagnosis, we established a course of action indicating the genes which are the most incriminated in the two types of sex inversion

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century