title: Comparison of age estimated from degree of racemization of aspartic acid, glutamic acid and alanine in the femur.
abstract: Aspartic acid (Asp) is generally used for estimation of age by measuring the degree of racemization. For other amino acids, however, there are few reports regarding the usefulness of the degree of racemization for the estimation of age. Accordingly, in this study using the femur (obtained from 21 cadavers) as the specimen, we measured the degree of racemization of glutamic acid (Glu) and alanine (Ala) along with Asp in the total amino acid (TAA) fraction as well as in acid-insoluble collagen-rich (IC) and acid-soluble peptide (SP) sub-fractions. We compared the degrees of racemization of each amino acid and the accuracy of the ages estimated from them. The degree of racemization and the reaction rate of racemization were ranked in the order of Asp > Glu > Ala in the TAA and IC fractions, but Asp > Ala > Glu in the SP fraction. It is noteworthy that the degrees of racemization differed between the three amino acids depending on the fraction tested. The correlation coefficient (r) between the degree of racemization and the chronological age was higher in the SP than in the TAA or IC fraction. Among three amino acids, Asp showed the highest correlation coefficient as predicted. The present study confirmed that Asp from the SP fraction is the best indicator for age estimation using racemization rates.
authors.affiliation: Department of Forensic Dental Medicine and Institute for Frontier Oral Science, Kanagawa Dental College, 82 Inaoka-cho, Yokosuka, Kanagawa 238-8580, Japan.
authors.forename: Susumu
authors.initials: S
authors.lastname: Ohtani
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Yamada
authors.forename: Toshiharu
authors.initials: T
authors.lastname: Yamamoto
authors.forename: Szilvia
authors.initials: S
authors.lastname: Arany
authors.forename: Kunio
authors.initials: K
authors.lastname: Gonmori
authors.forename: Naofumi
authors.initials: N
authors.lastname: Yoshioka
mesh_terms: D000293:Adolescent; D000328:Adult; D000365:Age Determination by Skeleton / Q000379:methods*; D000368:Aged; D000409:Alanine / Q000032:analysis*; D002102:Cadaver; D002849:Chromatography, Gas; D026603:D-Aspartic Acid / Q000032:analysis*; D005269:Femur / Q000737:chemistry*; D018732:Forensic Anthropology / Q000379:methods; D018698:Glutamic Acid / Q000032:analysis*; D006801:Humans; D008297:Male; D008875:Middle Aged; D013237:Stereoisomerism
chemical_list: D018698:Glutamic Acid; D026603:D-Aspartic Acid; D000409:Alanine