Genetics of Mendelian Diseases in Qatar

There are certain categories of diseases which are more prevalent in the Arab world due to increased rates of consanguinity in relatively isolated populations. The goal is to discover these mutations by using next-generation human genetics tools.

Study Overview

• Status: Completed
• Conditions: Mendelian Disorders

Detailed Description

There are certain categories of diseases which are more prevalent in the Arab world due to increased rates of consanguinity in relatively isolated populations. The goal is to discover these mutations by using next-generation human genetics tools. These include high-throughput sequencing and genotyping along with the necessary bioinformatics analyses that will lead to the discovery of the causes of most inherited diseases in the region.The secondary objective will be to build a comprehensive catalogue of genetic variation in the Arab world. This will include all detected mutations, not only the subset that are causing disease (from primary objective), but also known trait-altering mutations as well as general diversity on the DNA level among human populations of this region. This catalogue can become a widely useful resource for many projects down the road, as it relies on anonymizing individual samples and instead displaying data in aggregate as the cohorts of collected samples grow over the years.

The study will include all genetic disorders from all ethnic backgrounds but Mendelian disease for which a gene mutation has already been identified will be excluded.

Evidence of Mendelian Transmission determined by fulfilling one of the following criteria:

Multiple affected family members (at least first degree relative with disease) History of consanguinity Severe disease in newborn in the absence of family history Sydromic disease in single individuals Congenital abnormality affecting major organ system(s) Mendelianized extremes of common disease (eg sever familial diabetes/ obesity/ hypertension)

• Study Type: Observational
• Enrollment (Estimated): 400

Contacts and Locations

Study Locations

• Qatar
  • Doha, Qatar
    • Hamad Medical Corporation

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

physicians and by thorough review of the literature to establish that the disease is indeed Mendelian and with unknown gene.

Description

Inclusion Criteria:

• All included individuals must provide informed consent
• All genetic disorders are included
• All ethnic backgrounds are accepted
• Disease must be genetic with no evident environmental cause
• Evidence of Mendelian Transmission determined by fulfilling one of the following criteria:
• Multiple affected family members (at least first degree relative with disease)
• History of consanguinity
• Severe disease in newborn in the absence of family history
• Sydromic disease in single individuals
• Congenital abnormality affecting major organ system(s)
• Mendelianized extremes of common disease (eg sever familial diabetes/ obesity/ hypertension)

Exclusion Criteria:

• Individuals who do no consent to be included
• Mendelian disease for which a gene mutation has already been identified
• Individuals for which a molecular diagnosis has already been established by alternative method
• Disease for which an environmental factor is most likely the cause
• Disease for which late age of onset rule out Mendelian transmission
• Common diseases for which late age of onset rule out Mendelian transmission

Study Plan

How is the study designed?

Design Details

• Observational Models: Family-Based
• Time Perspectives: Prospective

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Next generation sequencing	Use next generation sequencing to detect novel disease causing mutations	1 hour

Collaborators and Investigators

• Sponsor: Weill Medical College of Cornell University
• Collaborators: Hamad Medical Corporation; Weill Cornell Medical College in Qatar
• Investigators: Principal Investigator: Ronald Crystal, MD, Weill Medical College of Cornell University

Study record dates

Study Major Dates

• Study Start (Actual): November 19, 2012
• Primary Completion (Actual): June 1, 2022
• Study Completion (Actual): February 1, 2025

Study Registration Dates

• First Submitted: November 22, 2013
• First Submitted That Met QC Criteria: December 19, 2013
• First Posted (Estimated): December 27, 2013

Study Record Updates

• Last Update Posted (Estimated): November 17, 2025
• Last Update Submitted That Met QC Criteria: November 13, 2025
• Last Verified: November 1, 2025

More Information

Terms related to this study

• Other Study ID Numbers: 13-00065 [JIRB]; 12217/12 (Other Identifier: HMC IRB)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO