Genetics and other factors in the aetiology of female pattern hair loss.

Pattern hair loss is the most common form of hair loss in both women and men. Male pattern hair loss, also termed male androgenetic alopecia (M-AGA), is an androgen-dependent trait that is predominantly genetically determined. Androgen-mediated mechanisms are probably involved in FPHL in some women but the evidence is less strong than in M-AGA; and other non-androgenic pathways, including environmental influences, may contribute to the aetiology. Genome-wide association studies (GWASs) have identified several genetic loci for M-AGA and have provided better insight into the underlying biology. However, the role of heritable factors in female pattern hair loss (FPHL) is largely unknown. Recently published studies have been restricted to candidate gene approaches and could not clearly identify any susceptibility locus/gene for FPHL but suggest the aetiology differs substantially from that of M-AGA. Hypotheses about possible pathomechanisms of FPHL as well as the results of the genetic studies performed to date are summarized. This article is protected by copyright. All rights reserved

Forensic DNA Phenotyping: Predicting human appearance from crime scene material for investigative purposes

Forensic DNA Phenotyping refers to the prediction of appearance traits of unknown sample donors, or unknown deceased (missing) persons, directly from biological materials found at the scene. "Biological witness" outcomes of Forensic DNA Phenotyping can provide investigative leads to trace unknown persons, who are unidentifiable with current comparative DNA profiling. This intelligence application of DNA marks a substantially different forensic use of genetic material rather than that of current DNA profiling presented in the courtroom. Currently, group-specific pigmentation traits are already predictable from DNA with reasonably high accuracies, while several other externally visible characteristics are under genetic investigation. Until individual-specific appearance becomes accurately predictable from DNA, conventional DNA profiling needs to be performed subsequent to appearance DNA prediction. Notably, and where Forensic DNA Phenotyping shows great promise, this is on a (much) smaller group of potential suspects, who match the appearance characteristics DNA-predicted from the crime scene stain or from the deceased person's remains. Provided sufficient funding being made available, future research to better understand the genetic basis of human appearance will expectedly lead to a substantially more detailed description of an unknown person's appearance from DNA, delivering increased value for police investigations in criminal and missing person cases involving unknowns. (C) 2015 Elsevier Ireland Ltd. All rights reserved

Hunting the genes in male-pattern alopecia: how important are they, how close are we and what will they tell us?

Androgenetic alopecia (AGA) is a highly heritable condition, and the most common form of hair loss in men. The phenotype is characterized by an androgen-dependent, progressive loss of hair from the scalp, which may commence during puberty. Up to 80% of European men experience some degree of androgen-dependent hair loss during their lifetime. Current treatment options for AGA have limited efficacy, and improved understanding of the underlying biological causes is required to facilitate novel therapeutic approaches. To date, molecular genetic studies have implicated 12 genomic regions in AGA and identified a number of candidate genes. The latter include those encoding the androgen receptor (AR), the histone deacetylases (HDAC) 4 and 9, and the WNT molecule WNT10A. However, the majority of contributing genetic risk factors still await identification. This review describes the current status of AGA genetic research. We discuss the strength of the genetic approach and anticipated developments in the field, and how these will facilitate the systematic unravelling of AGA pathobiology, a process which may lead to the identification of new therapeutic targets