LRHG Course: Lecture 15 - Novel genomic variants and genetic factors involved in Disorders of Sexual Development

January 25, 2023
Recording of the lecture is available below

The 15th lecture from the Logical Reasoning in Human Genetics (2.0) course was about "Novel genomic variants and genetic factors involved in Disorders of Sexual Development: Discovery to Translation", by Khouloud Rjiba, Doctor in the field of Biological Sciences and Biotechnology.

The lecture was then followed by a discussion between Dr. Rjiba and her Supervisor Dr. Soumaya Mougou Zerelli, along with the members of the LRHG steering committee: specialists from Institut Pasteur de Tunis - معهد باستور تونس and Columbia University, and a special visit from Dr. Inas Mazen, who discussed this topic by sharing her experience in Egypt.

Information about the Lecture:

The majority of individuals with disorders of sexual development (DSD) do not have a genetic etiology. However, in recent years a number of new genes causing DSD have been identified using the approach of next generation sequencing (NGS). We performed hole exome sequencing (WES) on a large cohort of 66 individuals with a wide range of DSD phenotypes all of Tunisian origin. Parental consanguinity was reported in 20% of individuals.

The genetic etiology was established in approximately 40% of the total cohort. The mutational spectrum of our patients is various. This includes rare and novel likely pathogenic variants in SRD5A2, SOX9, SOX8 ,ZNRF3, AR, LHCGR , MAMLD1  and HHAT genes . Interestingly, a homozygous variant in a gene (SART3), not known to be involved in DSD, coding for a novel spliceosomopathy affecting neuronal and testicular development was identified. DSD is relatively undervalued in Tunisia taken into account many reasons.

This data enrich our knowledge about the genetic etiology of DSD in Tunisia, the network of the proteins involved and emphasize the usefulness of WES to make an accurate genetic diagnosis for better genetic counseling and health care.

More about the lecturer:

Khouloud Rjiba is a doctor in Biological Sciences and Biotechnology and a researcher at The University Hospital Farhat Hached Sousse.

She is currently doing her research work at the Laboratory of Cytogenetics and Biology of Human reproduction at the Hospital of Farhat Hached Sousse, Tunisia. 
Khouloud has been working on the genetic basis of Disorders of sexual development in the Tunisian population to understand the genetic etiologies and offer knowledge-based genetic counseling since DSD is quite common in Tunisia and there is an unmet need in the population.
Her academic training and research experience have provided a respected background in Human genetics disorders, developmental biology, and genetic counseling.


We were pleased to have among us:

Pr. Harald H. H. Goring, Bennett Dyke & Jean MacCluer Endowed Professor, South Texas Diabetes and Obesity Institute & Department of Human Genetics.
Pr. Joseph Terwilliger, professor at the Department of Genetics and Development, Columbia University.
Dr. Yosr Hamdi Ph.D. in Molecular Medicine, Genetic Biologist at Institut Pasteur de Tunis.
Pr. Ghada Elkameh, Professor of Clinical Genetics, Coordinator of the Hereditary Blood Disorders and Genodermatoses Clinics and Research Teams, Human Genetics and Genome Research Division, National Research Centre.
Pr. Joseph H. Lee, Professor of Epidemiology at Columbia University Irving Medical Center.
Pr. Inas Mazen, professor at NRC and founder of DSD research in Egypt.

The LRHG course is in partnership with Institut Pasteur de Tunis - معهد باستور تونس . You can join us every first Wednesday of the month for a new and enlightening lecture ?‍?

More information on the course and recordings of the previous lectures can be found here.