Hematologically important mutations: X-linked chronic granulomatous disease (fourth update).

Area of Science:

• Immunology
• Genetics
• Molecular Biology

Background:

• Chronic granulomatous disease (CGD) is a primary immunodeficiency characterized by severe recurrent infections.
• It results from impaired function of the NADPH oxidase enzyme complex in phagocytes, crucial for microbial killing.
• The primary genetic defect often involves the CYBB gene, encoding the gp91phox (Nox2) subunit.

Purpose of the Study:

• To compile a comprehensive list of all identified mutations in the CYBB gene associated with X-linked CGD.
• To document benign polymorphisms in CYBB to aid in distinguishing disease-causing mutations.
• To include relevant mutations in the G6PD gene, as G6PD deficiency can mimic CGD symptoms by affecting NADPH availability.

Main Methods:

• Systematic literature review of identified mutations in the CYBB gene.
• Compilation and categorization of CYBB mutations and polymorphisms.
• Inclusion of data on G6PD gene mutations relevant to NADPH production.

Main Results:

• Detailed catalog of CYBB mutations, highlighting their prevalence in different populations.
• Identification of specific CYBB polymorphisms that may be mistaken for pathogenic mutations.
• Documentation of G6PD gene mutations that can lead to CGD-like symptoms due to NADPH deficiency.

Conclusions:

• This curated list of CYBB mutations provides a valuable resource for genetic counseling of families affected by X-linked CGD.
• Distinguishing pathogenic CYBB mutations from benign polymorphisms is critical for accurate diagnosis and management.
• Understanding the role of G6PD deficiency in CGD pathogenesis expands diagnostic considerations and potential therapeutic targets.