
Mild Canavan Disease: Revolutionizing Diagnosis with Genetic Testing
ASPA mutations reduce aspartoacylase and let N-acetylaspartic acid build up in the brain; long-read sequencing can catch the SVA_E insertion standard tests miss.

MD · MBA
Physician specializing in genetic analysis and personalized preventive medicine, and author of Outsmart Your Genes.
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).
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.

ASPA mutations reduce aspartoacylase and let N-acetylaspartic acid build up in the brain; long-read sequencing can catch the SVA_E insertion standard tests miss.

Core-like lesions in muscle fibers and weakness ranging from mild to respiratory involvement mark minicore myopathy, most often traced to RYR1 mutations.

A sharp drop in mitochondrial DNA inside tissues leaves cells short of energy, causing muscle weakness, neurological deficits and liver dysfunction; RRM2B is one cause.

Ten to 100 adenomatous polyps and later-onset colorectal cancer mark the MSH3-related form of AFAP; testing shapes colonoscopy schedules and alerts relatives.

Bone loss in the carpal and tarsal bones, joint deformities and skin nodules mark MONA; genetic testing can identify the mutation responsible.

Shortly after birth, MADD can cause hypoglycemia, metabolic acidosis and liver dysfunction; mutations in ETFA, ETFB and ETFDH confirm the diagnosis and guide diet.

Faulty glycosylation of alpha-dystroglycan weakens muscle tissue; MDDG ranges from severe congenital forms to milder adult-onset types, with FKRP variants often named.

Thin filaments in skeletal muscle need the protein nebulin, so NEB gene changes bring weakness in the hands and feet that shows up early in life.