Chronic Granulomatous Disease: Navigating the Genetic Maze
An inherited immunodeficiency in which white blood cells cannot make the reactive oxygen species needed to kill bacteria and fungi, with notes on carriers.
Brandon Colby, MD
MD · MBA
Physician specializing in genetic analysis and personalized preventive medicine, and author of Outsmart Your Genes.
About Brandon
Brandon Colby is a physician-expert in the fields of genetic analysis and Personalized Preventive Medicine. He holds an MD from the Mount Sinai School of Medicine, an MBA from Stanford University's Graduate School of Business, and a degree in Genetics from the University of Michigan.
Dr. Colby is the author of the book Outsmart Your Genes and has developed numerous technologies that improve the analysis, interpretation, and actionability of genome sequencing data. He is an Affiliate Specialist of the American College of Medical Genetics and Genomics (ACMG), an Associate of the American College of Preventive Medicine (ACPM), and a member of the National Society of Genetic Counselors (NSGC).
Education
- BA in Genetics with Honors, University of Michigan · 2000
- MD, Mount Sinai School of Medicine · 2004
- MBA, Stanford University Graduate School of Business · 2007
Affiliations & Memberships
- Affiliate Specialist, American College of Medical Genetics and Genomics (ACMG)
- Associate, American College of Preventive Medicine (ACPM)
- Member, National Society of Genetic Counselors (NSGC)
Articles by Brandon Colby, MD are reviewed for accuracy by Sequencing's medical and scientific team. This page is for informational purposes and does not constitute medical advice.
Articles by Brandon
Understanding Coenzyme Q10 Deficiency: The Role of Genetic Testing in Diagnosis and Management
Low CoQ10 hampers mitochondrial energy production, causing muscle weakness and fatigue; a link with hereditary hemochromatosis and gene testing features.
Cracking the Code: Understanding COL4A1 or COL4A2-Related Cerebral Small Vessel Disease
COL4A1 and COL4A2 encode type IV collagen in vessel walls; mutations and duplications weaken cerebral vessels and can lead to stroke, hemorrhage and cognitive decline.
Cracking the Code: Genetic Testing in Congenital Adrenal Hyperplasia
Most cases trace to CYP21A2 mutations causing 21-hydroxylase deficiency; over 100 known variants and technical limits explain some negative CAH results.
Cracking the Code: Understanding Congenital Bilateral Absence of Vas Deferens
Missing vas deferens on both sides blocks sperm transport and causes male infertility; about 80% of men with CBAVD carry at least one CFTR mutation.
Cracking the Code: Genetic Testing for Congenital Bile Acid Synthesis Defect
Toxic intermediates build up when bile acid production fails, so CBASD brings jaundice, poor growth and fat malabsorption in infancy; genetic testing can confirm it.
Congenital Fibrinogen Deficiency and Bleeding Risk
Without enough fibrinogen, blood cannot clot properly and bleeding episodes may be severe. Identifying the causative mutation shapes treatment and family counseling.
Congenital Hypothyroidism: Newborn Screening and Genes
An underactive thyroid at birth can affect growth and neurodevelopment. Newborn screening finds it within days, and gene testing separates transient from permanent forms.