Reference exome data for a Northern Brazilian population

Area of Science:

• Genomics
• Clinical Genetics
• Population Genetics

Background:

• Exome sequencing is vital for diagnosing rare genetic disorders and analyzing complex diseases.
• A lack of population-specific reference data hinders accurate variant interpretation in clinical settings.
• This study addresses the need for localized genomic data in Brazil.

Purpose of the Study:

• To create a comprehensive catalog of exomic variants from a Brazilian cohort.
• To provide essential reference data for improving rare disease diagnosis in Brazil.
• To identify pathogenic variants using established clinical guidelines.

Main Methods:

• Whole exome sequencing was performed on 45 infants from Rio Grande do Nord, Brazil.
• Sequence data were processed using an intersect-then-combine (ITC) approach with GATK and SAMtools.
• Variant annotation and pathogenicity assessment followed American College of Medicine Genetics and Genomics (ACMG) guidelines.

Main Results:

• A total of 612,761 variants were identified across the cohort.
• This included 559,448 single nucleotide variants (SNVs) and 53,313 insertion/deletions.
• 185 variants (0.32%) were classified as pathogenic or likely pathogenic based on ACMG criteria.

Conclusions:

• The generated variant catalog serves as a valuable resource for rare disease diagnosis in Brazil.
• This population-specific data enhances the accuracy of variant interpretation for Brazilian patients.
• The study underscores the importance of localized genomic databases in clinical genetics.