Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2008-4-25
pubmed:abstractText
Eumelanin (brown/black melanin) and pheomelanin (red/yellow melanin) in human hair can be quantified using chemical methods or approximated using spectrophotometric methods. Chemical methods consume greater resources, making them less attractive for epidemiological studies. This investigation sought to identify the spectrophotometric measures that best explain the light-dark continuum of hair color and the measure that is best able to distinguish red hair from nonred hair. Genetic analysis was performed on these two measures to determine the proportion of genetic and environmental influences on variation in these traits. Reflectance curves along the visible spectrum and subjective ratings of hair color were collected from 1730 adolescent twin individuals. Discriminant class analyses were performed to determine the spectrophotometric measure that could best proxy for eumelanin and pheomelanin quantities. The ratio of light reflected in the green portion of the spectrum to that reflected in the red portion of the spectrum was best able to distinguish red hair from nonred hair. Melanocortin 1 receptor (MC1R) genotype explained some, but not all, variation in this measure. Light absorbed in the red portion of the spectrum was best able to explain the light-dark continuum of hair color. Variance components analysis showed that there were qualitatively different genetic influences between males and females for the light-dark continuum of hair. Our results show that spectrophotometric measures approximating variation in eumelanin and pheomelanin may be considered as an alternative to chemical methods in larger epidemiological studies.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0031-8655
pubmed:author
pubmed:issnType
Print
pubmed:volume
84
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
719-26
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed-meshheading:18435620-Adolescent, pubmed-meshheading:18435620-Analysis of Variance, pubmed-meshheading:18435620-Australia, pubmed-meshheading:18435620-Child, pubmed-meshheading:18435620-Cohort Studies, pubmed-meshheading:18435620-Environment, pubmed-meshheading:18435620-Female, pubmed-meshheading:18435620-Genetic Variation, pubmed-meshheading:18435620-Genotype, pubmed-meshheading:18435620-Hair, pubmed-meshheading:18435620-Hair Color, pubmed-meshheading:18435620-Humans, pubmed-meshheading:18435620-Likelihood Functions, pubmed-meshheading:18435620-Male, pubmed-meshheading:18435620-Melanins, pubmed-meshheading:18435620-ROC Curve, pubmed-meshheading:18435620-Receptor, Melanocortin, Type 1, pubmed-meshheading:18435620-Sex Factors, pubmed-meshheading:18435620-Spectrophotometry, pubmed-meshheading:18435620-Twins, Dizygotic, pubmed-meshheading:18435620-Twins, Monozygotic
pubmed:articleTitle
Spectrophotometric methods for quantifying pigmentation in human hair-influence of MC1R genotype and environment.
pubmed:affiliation
Genetic Epidemiology Unit, Queensland Institute of Medical Research, Brisbane, Qld, Australia. sri.shekar@qimr.edu.au
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural, Twin Study, Validation Studies