Genetic Epidemiology, Psychiatric Genetics, Asthma Genetics and Statistical Genetics Laboratories investigate the pattern of disease in families, particularly identical and non-identical twins, to assess the relative importance of genes and environment in a variety of important health problems.
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PMID
18435620
TITLE
Spectrophotometric methods for quantifying pigmentation in human hair-influence of MC1R genotype and environment.
ABSTRACT
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.
DATE PUBLISHED
2008 May-Jun
HISTORY
PUBSTATUS PUBSTATUSDATE
pubmed 2008/04/26 09:00
medline 2008/09/13 09:00
entrez 2008/04/26 09:00
AUTHORS
NAME COLLECTIVENAME LASTNAME FORENAME INITIALS AFFILIATION AFFILIATIONINFO
Shekar SN Shekar Sri N SN Genetic Epidemiology Unit, Queensland Institute of Medical Research, Brisbane, Qld, Australia. sri.shekar@qimr.edu.au
Duffy DL Duffy David L DL
Frudakis T Frudakis Tony T
Montgomery GW Montgomery Grant W GW
James MR James Michael R MR
Sturm RA Sturm Richard A RA
Martin NG Martin Nicholas G NG
INVESTIGATORS
JOURNAL
VOLUME: 84
ISSUE: 3
TITLE: Photochemistry and photobiology
ISOABBREVIATION: Photochem. Photobiol.
YEAR:
MONTH:
DAY:
MEDLINEDATE: 2008 May-Jun
SEASON:
CITEDMEDIUM: Print
ISSN: 0031-8655
ISSNTYPE: Print
MEDLINE JOURNAL
MEDLINETA: Photochem Photobiol
COUNTRY: United States
ISSNLINKING: 0031-8655
NLMUNIQUEID: 0376425
PUBLICATION TYPE
PUBLICATIONTYPE TEXT
Journal Article
Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't
Twin Study
Validation Studies
COMMENTS AND CORRECTIONS
GRANTS
GRANTID AGENCY COUNTRY
CA88363 NCI NIH HHS United States
GENERAL NOTE
KEYWORDS
MESH HEADINGS
DESCRIPTORNAME QUALIFIERNAME
Adolescent
Analysis of Variance
Australia
Child
Cohort Studies
Environment
Female
Genetic Variation
Genotype
Hair chemistry
Hair Color genetics
Humans genetics
Likelihood Functions genetics
Male genetics
Melanins chemistry
ROC Curve chemistry
Receptor, Melanocortin, Type 1 genetics
Sex Factors genetics
Spectrophotometry genetics
Twins, Dizygotic genetics
Twins, Monozygotic genetics
SUPPLEMENTARY MESH
GENE SYMBOLS
CHEMICALS
REGISTRYNUMBER NAMEOFSUBSTANCE
0 Melanins
0 Receptor, Melanocortin, Type 1
0 pheomelanin
12627-86-0 eumelanin
OTHER ID's