Human AMELX (Amelogenin, X isoform) ELISA Kit

Background. It is increasingly emphasized that the influence of a host's factors in the etiology of dental caries are of most interest, particularly those concerned with genetic aspect. Objectives. The aim of the study was to analyze the genotype and allele frequencies of single nucleotide polymorphisms (SNPs) in AMELX, AMBN, TUFT1, TFIP11, MMP20 and KLK4 genes and to prove their association with dental caries occurrence in a population of Polish children. Material and methods. The study was performed in 96 children (48 individuals with caries -"cases" and 48 free of this disease -"controls"), aged 20-42 months, chosen out of 262 individuals who had dental examination performed and attended 4 day nurseries located in Poznan (Poland). From both groups oral swab was collected for molecular evaluation. Eleven selected SNPs markers were genotyped by Sanger sequencing. Genotype and allele frequencies were calculated and a standard chi(2) analysis was used to test for deviation from Hardy-Weinberg equilibrium. The association of genetic variations with caries susceptibility or resistance was assessed by the Fisher's exact test and p <= 0.05 was considered statistically significant. Results. Five markers were significantly associated with caries incidence in children in the study: rs17878486 in AMELX (p < 0.0001), rs34538475 in AMBN (p < 0.0001), rs2337360 in TUFT1 (p < 0.0001), and rs2235091 (p = 0.0085) and rs198969 (p = 0.0069) in KLK4. Genotype and allele frequencies indicated both risk and protective variants for these markers. Conclusions. Single nucleotide polymorphisms in AMELX, AMBN, TUFT1, KLK4 genes may be considered as a risk factor for dental caries occurrence in Polish children.

Amelogenin genes are located on both X and Y sex chromosomes in humans and are a major focus of DNA-based sex estimation methods. Amelogenin proteins, AMELX_HUMAN and AMELY_HUMAN, are expressed in the tooth organ and play a major role in mineralization of enamel, the most taphonomically resistant, archaeologically persistent human tissue. We describe shotgun liquid chromatography mass spectrometry analysis of 40 enamel samples representing 25 individuals, including modern third molars and archaeological teeth from open-air contexts including permanent adult (400 to 7300 BP) and deciduous teeth (100 to 1000 BP). Peptides specific to the X-chromosome isoform of amelogenin were detected in all samples. Peptides specific to the sexually dimorphic Y-chromosome isoform were also detected in 26 samples from 13 individuals, across all time periods, including previously unsexed deciduous teeth from archaeological contexts. While the signal of each gene product can vary by more than an order of magnitude, we show close agreement between osteological and amelogenin-based sex estimation and thus demonstrate that the protein-based signal can be obtained reliably from open-air archaeological contexts dating to at least 7300 years ago. While samples with AMELY_HUMAN peptides are unambiguously male, samples with no AMELY_HUMAN signal may either be low signal male false negative samples or female samples. In order to estimate sex in these samples we developed a probability curve of female sex as a function of the logarithm of AMELX_HUMAN signal (p < 0.0001) using logistic regression. This is also the first demonstration using proteomics to estimate sex in deciduous teeth and pushes back the application of the method to teeth that are at least 7300 years old.