Consanguinity and Occurrence of Monogenic Diseases in a Single Tertiary Centre in Riyadh, Saudi Arabia: A 2 Years Cross-Sectional Study

Lamia K Alshamlani,1 Dana S Alsulaim,1 Raghad S Alabbad,1 Ahad A Alhoshan,1 Joud F Alkhoder,1 Norah S Alsaleh,2 Mohammed Almannai,1– 3 Faroug Ababneh,2 Manal Algattan,4 Lojain Alsini,4 Abdulrahman Faiz Alswaid,2 Wafaa M Eyaid,1– 3 Fuad Al Mutairi,1– 3 Muhammad Umair,3 Majid Alfadhel1– 3 1College of Medicine, King Saud bin Abdulaziz University for Health Sciences (KSAU-HS), King Abdulaziz Medical City, Ministry of National Guard Health Affairs (MNG-HA), Riyadh, Saudi Arabia; 2Genetics and Precision Medicine Department (GPM), King Abdullah Specialized Children Hospital (KASCH), King Saud Bin Abdulaziz University for Health Sciences, King Abdulaziz Medical City, Ministry of National Guard Health Affairs (MNG-HA), Riyadh, Saudi Arabia; 3Medical Genomics Research Department, King Abdullah International Medical Research Center (KAIMRC), King Saud Bin Abdulaziz University for Health Sciences, Ministry of National Guard Health Affairs (MNGH), Riyadh, Saudi Arabia; 4Pathology and Laboratory Medicine Department, King Abdulaziz Medical City, Ministry of National Guard Health Affairs, Riyadh, Saudi ArabiaCorrespondence: Majid Alfadhel, Genetics and Precision Medicine Department (GPM), King Abdullah Specialized Children’s Hospital, King Abdulaziz Medical City, P.O Box 22490, Riyadh, 11426, Saudi Arabia, Tel +00 966 11 805 3560, Fax +00 966 11 805 5555, Email [email protected]: Consanguinity, or the practice of marrying close relatives, is a common cultural tradition in Saudi Arabia, with rates among the highest in the world. This practice has significant implications for the prevalence and distribution of major single genetic defects and chromosomal abnormalities within the Saudi population.Methods: Herein, using the BESTCare electronic medical record system (designed to streamline hospital operations, enhance patient care, and improve the overall efficiency of healthcare services; bestcare.ezcaretech.com) in a single tertiary centre, King Abdullah Specialized Children Hospital (KASCH) in Riyadh, Saudi Arabia, we performed a cross-sectional study for all patients referred to the hospital from the 1st January 2020 until 1st January 2022.Results: The present study, which included 1100 individuals, found a high prevalence of consanguinity (64%) and a significant proportion of third-degree relatives (69%). The mean age of participants was 12.24 years, and the diagnostic rate using advanced molecular genetics techniques was 45%, with whole exome sequencing (WES) being the most common method (43%). The study also noted a significant delay in diagnosis for more than a year in 16% of cases, with a common neurodevelopmental phenotype (18%).Conclusion: In conclusion, we revealed the prevalence of consanguineous marriages in the KASCH hospital in Riyadh, Saudi Arabia. We also highlighted the most frequently referred phenotype. These findings are consistent with previous research on the prevalence and impact of consanguinity on rare genetic disorders.Keywords: consanguinity, genetic disorders, autosomal recessive disorders, Saudi Arabia, prevalence of single gene disorder, chromosomal abnormalities