Hematologically important mutations: The autosomal forms of chronic granulomatous disease (third update)

Area of Science:

• Immunology
• Genetics
• Molecular Biology

Background:

• Chronic granulomatous disease (CGD) is a primary immunodeficiency characterized by severe, recurrent bacterial and fungal infections.
• CGD results from inherited defects in the leukocyte NADPH oxidase enzyme complex, crucial for pathogen killing by phagocytes.
• The enzyme complex comprises subunits encoded by autosomal genes (CYBA, NCF1, NCF2, NCF4) and X-linked genes.

Purpose of the Study:

• To comprehensively list and describe all identified mutations in genes associated with Chronic Granulomatous Disease (CGD).
• To consolidate information on genetic defects causing CGD, including mutations in CYBA, NCF1, NCF2, NCF4, CYBC1, and RAC2 genes.
• To provide a resource for understanding the genetic basis of CGD and its impact on immune function.

Main Methods:

• Literature review and compilation of reported mutations in CGD patients.
• Analysis of gene sequences encoding NADPH oxidase subunits and related proteins.
• Inclusion of mutations in CYBC1 and RAC2, recently identified as causative for CGD or CGD-like symptoms.

Main Results:

• Detailed cataloging of mutations within the CYBA, NCF1, NCF2, and NCF4 genes responsible for CGD.
• Identification and documentation of mutations in the CYBC1 gene, essential for gp91phox (Nox2) expression.
• Documentation of mutations in the RAC2 gene, leading to CGD-like symptoms due to impaired NADPH oxidase activation.

Conclusions:

• Mutations in CYBA, NCF1, NCF2, NCF4, CYBC1, and RAC2 genes collectively explain the genetic basis of Chronic Granulomatous Disease.
• Understanding these genetic mutations is critical for accurate diagnosis, genetic counseling, and potential therapeutic strategies for CGD patients.
• This review serves as a comprehensive genetic compendium for CGD, facilitating further research and clinical management.