#ExistInterpData>Background Information for Chronic Granulomatous Disease (NCF1) Exon 2 GT Deletion:
Characteristics of chronic granulomatous disease (CGD):
A primary immunodeficiency disorder characterized by recurrent, severe bacterial and fungal infections of the skin, lymph nodes, liver, lungs, bones, or visceral organs. Dysregulated inflammatory responses result in granulomas.
Incidence: Approximately 1 in 250,000 births.
Inheritance: Autosomal recessive.
Cause: Autosomal recessive CGD may result from mutations in NCF1 (25 percent), CYBA (<5 percent), NCF2 (<5 percent) and NCF4 (very rare). Pathogenic mutations in the CYBB gene result in X-linked CGD that accounts for 60-70 percent of all CGD.
Clinical Sensitivity: 18 percent for CGD.
Methodology: High Resolution Melt Analysis to detect the GT deletion in exon 2 of NCF1.
Analytical Sensitivity: 99 percent for homozygous GT deletion, 90 percent for heterozygous GT deletion.
Analytical Specificity: 99 percent.
Limitations: Mutations other than the NCF1 exon 2 GT deletion are not evaluated. Rare diagnostic errors can result due to primer-site mutations. Because of potential recombination between NCF1 and its pseudogenes, the lack of detection of the GT deletion in exon 2 does not rule out carrier status for autosomal recessive CGD.
Counseling and informed consent are recommended for genetic testing. Consent forms are available online at www.aruplab.com.
See Compliance Statement C: www.aruplab.com/CS