This information is provided by the National Institutes of Health (NIH) Genetic and Rare Diseases Information Center (GARD).
Pili annulati is a hair disorder. In pili annulati, affected hair has a pattern of light and dark banding. People with pili annulati may
describe their hair as “striped” or as having silvery beads. Pili annulati typically involves 20-80% of scalp hair, however it can involve
facial and body hair as well. Affected hairs
may be more prone to breakage. Pili annulati can present in infancy,
childhood, or later in life. It can be seen with
the naked eye, however it may be more difficult to see in people with
dark hair. Diagnosis is confirmed by polariscopic and/or electron
microscopic examination of affected hairs. The
condition runs in an autosomal dominant fashion in some families.
Reduced penetrance and variable expression has been described. Sporadic
cases have also been reported.
For more information, visit GARD.