Ectodermal Dysplasia 7 (KRTHB5): Hair and Nail Signs
Brittle hair and malformed or missing nails mark this hair/nail type, which research has traced to a mutation in the KRTHB5 gene that shapes both structures.
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
What Causes Ectodermal Dysplasia 9? The KRTHB5 Gene
Sparse, brittle or absent hair and underdeveloped nails define the hair/nail type, and DNA analysis looks for the KRTHB5 mutation identified in a pivotal study.
Epilepsy: Idiopathic Generalized, Susceptibility to, 12 - The Genetic Connection
Idiopathic generalized epilepsy is thought to have a strong genetic component; variants in RYR3, a calcium-signaling gene, are a possible susceptibility factor.
Facial Paresis, Hereditary Congenital, 3: Unveiling Genetic Insights
Weakness of the facial muscles is present from birth in HCFP3, which passes in an autosomal dominant pattern; recent work adds neck and shoulder girdle weakness.
Focal Facial Dermal Dysplasia Type IV: Unraveling the Genetic Threads of a Rare Disorder
Preauricular lesions on the face are the hallmark of FFDD4, sometimes with eye, ear or skeletal anomalies; genetic testing can confirm it and guide family planning.
Genetic Insights into Glucocorticoid Deficiency 4: Unveiling the Mysteries of a Rare Disorder
Cortisol production falls short in GCCD4, bringing fatigue, weight loss, low blood pressure and frequent infections; testing points to MC2R, MRAP and related genes.
Hereditary Spastic Paraplegia 53: Diagnosis and COQ7
Corticospinal tract degeneration drives the leg weakness of HSP 53, where a novel homozygous COQ7 variant has been described and can be confirmed by DNA testing.
Herpes Simplex Encephalitis: Unraveling Genetic Susceptibility
Fever, headache, confusion and seizures can follow HSV-1 infection of the brain. Variants in the TLR3/TRIF pathway weaken the interferon and IL-15 response.