Decoding GLB1-Related Disorders: Understanding, Diagnosing, and Genetic Testing
Beta-galactosidase deficiency from GLB1 mutations causes GM1 gangliosidosis and mucopolysaccharidosis type IVB; enzyme assays plus sequencing separate the two.
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, Diagnosing, and Using Genetic Testing for GM1-gangliosidosis, Type I with Cardiac Involvement
Seizures, developmental delay, heart valve problems and corneal clouding mark GM1-gangliosidosis; low beta-galactosidase activity and GLB1 findings confirm it.
Decoding the Mysteries of Adult-Onset GM2-Gangliosidosis
Ataxia, tremor and neuropsychiatric symptoms can start in the second or third decade of life; HEXA and HEXB analysis confirms adult-onset GM2-gangliosidosis.
Cracking the Code: Understanding and Diagnosing X-Linked Chronic Granulomatous Disease Variant
Faulty gp91phox leaves patients open to severe infection; copy number variants and skewed X-inactivation complicate CYBB analysis in the X-CGD variant.
Decoding the Mystery of Hereditary Haemorrhagic Telangiectasia 1: Genetic Testing and Beyond
Nosebleeds, gut bleeding and arteriovenous malformations follow the ACVRL1/ALK1 mutations behind HHT1; confirming the variant lets relatives be screened early.
Decoding Haemorrhagic Telangiectasia 2: Genetic Testing Unravels the Mystery
Curaçao criteria plus gene analysis identify HHT2, an autosomal dominant condition in which ENG, ACVRL1, SMAD4 or EPHB4 changes distort blood vessel formation.
Hemophilia B (Christmas Disease): F9 Gene Testing
Known as Christmas disease, this X-linked bleeding disorder stems from F9 gene mutations, and a novel missense variant in one report shows why sequencing matters.
Hepatorenocardiac Degenerative Fibrosis: Diagnosis
Fibrous tissue accumulates in the liver, kidneys and heart in hepatorenocardiac degenerative fibrosis, diagnosed through clinical exams, imaging and laboratory tests.