Analysis of DNA in Hair Fibers
March 2003
in “
PubMed
”
TLDR Small amounts of DNA can be found in the hair shaft, especially near the root, but it decreases with hair treatments and washing.
The study from 2003, "Analysis of DNA in hair fibers," described the extraction and identification of DNA from human hair shafts. The DNA was found in low levels in the hair shaft and was identified using polymerase chain reaction amplification of the human leukocyte antigen (HLA)-DQA1 locus. The DNA was found to reside in the cuticle portion of the hair shaft. The levels of DNA were higher at the root-end compared to the tip-end of hair and were lower after permanent colorant treatment. DNA was lost with surfactant washing, with increased loss occurring with prolonged or an increasing number of washes. The results suggested that small amounts of residual DNA remain after differentiation.