Genetic Analysis of a Case of Sotos Syndrome with Suspected Germinal Mosaicism in Mother.

This study is to identify the pathogenic mutation of a child with Sots syndrome and provide prenatal diagnosis for his pregnant mother. Chromosome microarray technology was used to detect whether there were minor deletions/duplication in patients' chromosomes. The gene mutation of patients was screened by next-generation sequencing technology, and it was verified by Sanger sequencing. Prenatal diagnosis of the fetus was conducted according to the selected pathogenic sites, and genetic counseling was conducted for her parents. Chromosome microarray results showed that there was no minor deletion in a chromosome 5q35 region, and the second-generation sequencing results showed that there was a c.4138delG heterozygous mutation in the patient's NSD1 gene, and the pathogenic of this mutation was not reported in related databases. Sanger sequencing found that there was a c.4138delG heterozygous mutation in the NSD1 gene of the patient and her parents' genotype at this locus was wild type. The prenatal gene test results indicated that there was heterozygous mutation of NSD1 gene c.4138delG in the fetus, so it was suggested to terminate the pregnancy. Gentling results indicated that the fetus and the patient inherited the same maternal chromosome 5. The heterozygous mutation of NSD1 gene c.4138delG is the pathogenic mutation of this Sots syndrome patient, and the mother may be germinal mosaicism.

Evaluation of the genetic parameters and mutation analysis of 22 STR loci in the central Chinese Han population.

At present, the Han nationality is China's main ethnic group and also the most populous nation in the world. This is a great resource to study microsatellite mutations and for the study of ethnogeny. The aim of this study is to investigate the genetic polymorphisms and mutations of 22 autosomal STR loci in 2475 individuals from Henan province, China. DNA is amplified and genotyped using PowerPlex™24 system. The gene frequencies, forensic parameters, and the mutation rate of the 22 STR loci are analyzed. A total of 295 alleles are observed in this Henan Han population, and the allelic frequencies ranged from 0.0003 to 0.5036. In order to investigate the genetic relationships between the Henan Han and the other 14 different populations, our present data were compared with previously published data for the same 15 STR loci. The results indicated that the Henan Han had closer genetic relationships the groups including Minnan Han, Maonan, Yi and Guangdong Han groups while the South morocco population, the Moroccan population, the Malay group, and the Uigur stand away from Henan Han. Except of D2S441, D13S317, PentaE, D2S1338, D5S818, TPOX and D19S433, the mutation events are found in the other 15 STR loci. A total of 40 mutation events are observed in the 15 STR loci. The mutation rates are ranged from 0 to 4.85 × 10-3. In this study, 39 mutations are single-step mutations, and only one at FGA comprised two steps. STR mutation is commonly existed in paternity testing, while there are no STR mutation studies of the 22 STR loci in the Henan Han population. It is of great importance in forensic individual discrimination and paternal testing.