Cracking the Code: Genetic Testing for Complement Component 4b Deficiency
Impaired opsonization leaves pathogens poorly cleared when the C4B gene is faulty, and sequencing that gene separates this deficiency from similar immune disorders.
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
Complex Cortical Dysplasia with Other Brain Malformations 5: Unraveling the Genetic Mysteries
Seizures, intellectual disability and developmental delays mark CDCBM5, a rare disorder of cortical development; genetic testing supports diagnosis and counseling.
Cracking the Code: Understanding Complex Cortical Dysplasia with Other Brain Malformations 6 through Genetic Testing
A TUBB gene variant found in a child with CDCBM6 expanded what is known about this rare malformation, which brings epilepsy and developmental delay.
Cracking the Code: Genetic Testing and Cone-rod Dystrophy 16
Trouble seeing in low light that progresses to loss of color and central vision points to CRD16, where CFAP410 mutations help confirm the diagnosis.
Cracking the Code: Understanding Congenital Cataract-Hearing Loss-Severe Developmental Delay Syndrome Through Genetic Testing
Cataracts at birth, hearing loss, hypotonia and severe developmental delay occur together in this rare syndrome, with low serum copper and ceruloplasmin also reported.
Decoding the Dilemma: Understanding Congenital Diarrhea 6
Severe diarrhea from the newborn period, failure to thrive and lifelong nutritional support mark CD6, which has been linked to mutations in the EPCAM gene.
CDG-Ir and the ALG1 Gene: Testing and Care
Mutations in the ALG1 gene cause CDG-Ir, with developmental delays, neurological issues and metabolic abnormalities. Testing supports early diagnosis and counseling.
Charting the Course: Understanding Congenital Heart Defects, Multiple Types, 2
Structural heart problems present at birth define this form, which one study tied to a novel ZIC3 mutation in a Chinese family; prenatal DNA testing can detect it early.