Dataset Information

Optimal Processing for Proteomic Genotyping of Single Human Hairs

ABSTRACT: The human hair proteome offers new insight in the field of human identification. Hair often contains DNA that has been degraded due to the process of cornification. The smaller fragments of DNA present a challenge for obtaining useful information concerning the identity of the donor. Proteomic genotyping offers an alternative approach which starts with protein, a biomolecule abundant in the hair shaft. Nonsynonymous single nucleotide polymorphisms may be detected in the sequence of these proteins, allowing the inference of SNP genotypes. Population genetics-based information from these genotypes may be used to calculate random match probability or even infer ancestry. The current challenge of this research is to optimize processing chemistry in order to maximize genetic information from a single human hair shaft. Results indicate that optimal conditions for proteomic analysis of a single human hair include 6 hrs of reduction with 100 mM dithiothreitol at room temperature, alkylation with 200 mM iodoacetamide for 45 min, and 6 hrs of digestion with two 1:50 (enzyme:protein) additions of stabilized trypsin at room temperature, with stirring incorporated into all three steps. Our final conditions using optimized temperatures and incubation times for disulfide reduction and protein digestion produced random match probabilities of up to 1 in 624 million from a single hair with a median value of 1 in 1.1 million, compared to a maximum random match probability of 1 in 1380 and a median value of 1 in 24 for the original processing method.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Hair Shaft

SUBMITTER: Glendon Parker

LAB HEAD: Glendon John Parker

PROVIDER: PXD016155 | Pride | 2020-06-10

REPOSITORIES: Pride

ACCESS DATA

Publications

Optimal processing for proteomic genotyping of single human hairs.

Goecker Zachary C ZC Salemi Michelle R MR Karim Noreen N Phinney Brett S BS Rice Robert H RH Parker Glendon J GJ

Forensic science international. Genetics 20200525

The use of hair evidence for human identification is undergoing considerable improvement through the adoption of proteomic genotyping. Unlike traditional microscopic comparisons, protein sequencing provides quantitative and empirically based estimates for random match probability. Non-synonymous SNPs are translated as single amino acid polymorphisms and result in genetically variant peptides. Using high resolution mass spectrometry, these peptides can be detected in hair shaft proteins and used ...[more]

PMID: 32505640

Similar Datasets

Project description:Increasing evidence suggests that microRNAs may play important roles in regulating self-renewal and differentiation in mammalian stem cells (SCs). Here, we explore this issue in skin. We first characterize microRNA expression profiles of skin SCs versus their committed proliferative progenies and identify a microRNA subset associating with “stemness”. Of these, miR-125b is dramatically downregulated in early SC-progeny. We engineer an inducible mice system and show that when miR-125b is sustained in SC-progenies, tissue balance is reversibly skewed towards stemness at the expense of epidermal, oil-gland and HF differentiation. Using gain-and-loss of function in vitro, we further implicate miR-125b as a repressor of SC differentiation. In vivo, transcripts repressed upon miR-125b induction are enriched >700% for predicted miR-125b targets normally downregulated upon SC-lineage commitment. We verify some of these miR-125b targets, and show that Blimp1 and VDR in particular can account for many tissue imbalances we see when miR-125b is deregulated. We used microarrays to compare the global miRNA expression profile of P4 stage hair follicle ORS cells from DTG (K14-rtTA,TRE-miR-125b) and control littermates. Hair follicle cells were isolated from P4 Backskin (Dox since P3 for 24hrs) of DTG (K14-rtTA/TRE-miR-125b/K14-H2BGFP), TRE (TRE-miR-125b/K14-H2BGFP), KrtA (K14-rtTA/K14-H2BGFP) as following: interfollicular epidermis sheet was pealed from hair follicle & dermis after dispase treatment.The hair follicle & dermis were first digested by collagenase (Sigma). Intact hair follicles were separated from dermal cells by low speed spinning (20g). The hair follicles were then digested by Trypsin and filtered by 40 µm cell strainers. The isolated hair follicle cells were FACS sorted. During FACS, cells were first gated against CD34 (endothelial cells), CD45 (immune cells), CD114 (melanocytes) and DAPI (dead cells). ORS cells were sorted from the remaining cells as α6HiGFPHi.

Dataset Information

Optimal Processing for Proteomic Genotyping of Single Human Hairs

Publications

Optimal processing for proteomic genotyping of single human hairs.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure