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The article focuses on a study which reconstructs the rate of genetic recovery of the population of the hermaphroditic mangrove, Avicennia alba, in Mekong Delta 30 years after the use of Agent Orange, which is a mixture of phenoxyl herbicides. It evaluates the age of Avicennia alba with the use of models based on internode growth and genotypes samples for six microsatellite loci. It also compares the reconstructed evolution of genetic diversity since local extinction with the genetic diversity of an unaffected population from Thailand. Results show that genetic diversity of the population is increasing in Mekong Delta. However, the population is reaching an asymptotic level that is comparable to the Thai population.

Objective: To describe two unrelated Thai patients with suspected 5α-reductase type 2 deficiency and perform mutation analysis of the SRD5A2 gene. Design: Case report. Setting: A pediatric endocrinology clinic at a university hospital. Patient(s): Two unrelated patients with 46,XY karyotype, born with ambiguous genitalia, were studied. One was reared as a boy and the other was reared as a girl. Intervention(s): The entire coding regions of the SRD5A2 gene were assessed by polymerase chain reaction (PCR) and sequencing analysis. Main Outcome Measure(s): Molecular characterization of the SRD5A2 gene. Result(s): Four different pathogenic mutations (three missense and one nonsense) were identified. These were located at exon 1 (p.Q6X and p.L20P), exon 3 (p.G183S), and exon 4 (p.G203S). The T>C transition (c.59T>C) resulting in a leucine-to-proline substitution at codon 20 (p.L20P) has not been previously described and was not detected in 100 unaffected, ethnic-matched control chromosomes. In addition, p.G183S, previously identified only among patients from mixed African–European ancestry and in the Dominican Republic, was also detected in a Thai patient. Conclusion(s): This study demonstrates that the SRD5A2 gene is responsible for 5α-reductase type 2 deficiency across different populations and emphasizes the important role of genetic testing for the definite diagnosis and genetic counseling before gender assignment or any surgical intervention. [Copyright &y& Elsevier]