Genetic analysis and reproductive intervention of 7 families with gonadal mosaicism for Duchenne muscular dystrophy / 中华医学遗传学杂志

OBJECTIVE@#To explore the genetic basis for 7 families with gonadal mosaicism for Duchenne muscular dystrophy (DMD).@*METHODS@#For the 7 families presented at the CITIC Xiangya Reproductive and Genetic Hospital from September 2014 to March 2022, clinical data were collected. Preimplantation genetic testing for monogenic disorders (PGT-M) was carried out for the mother of the proband from family 6. Peripheral venous blood samples of the probands, their mothers and other patients from the families, amniotic fluid samples from families 1 ~ 4 and biopsied cells of embryos cultured in vitro from family 6 were collected for the extraction of genomic DNA. Multiplex ligation-dependent probe amplification (MLPA) was carried out for the DMD gene, and short tandem repeat (STR)/single nucleotide polymorphism (SNP)-based haplotypes were constructed for the probands, other patients, fetuses and embryos.@*RESULTS@#The results of MLPA showed that the probands and the fetuses/probands' brothers in families 1 ~ 4, 5, 7 had carried the same DMD gene variants, whilst the probands' mothers were all normal. The proband in family 6 carried the same DMD gene variant with only 1 embryo (9 in total) cultured in vitro, and the DMD gene of the proband's mother and the fetus obtained through the PGT-M were normal. STR-based haplotype analysis showed that the probands and the fetuses/probands' brothers in families 1 ~ 3 and 5 have inherited the same maternal X chromosome. SNP-based haplotype analysis showed that the proband from family 6 has inherited the same maternal X chromosome with only 1 embryo (9 in total) cultured in vitro. The fetuses in families 1 and 6 (via PGT-M) were both confirmed to be healthy by follow up, whilst the mothers from families 2 and 3 had chosen induced labor.@*CONCLUSION@#Haplotype analysis based on STR/SNP is an effective method for judging gonad mosaicism. Gonad mosaicisms should be suspected for women who have given births to children with DMD gene variants but with a normal peripheral blood genotype. Prenatal diagnosis and reproductive intervention may be adapted to reduce the births of further affected children in such families.

Analysis and prenatal diagnosis of FMR1 gene mutations among patients with unexplained mental retardation / 中华医学遗传学杂志

OBJECTIVE@#To analyze the (CGG)n repeats of FMR1 gene among patients with unexplained mental retardation.@*METHODS@#For 201 patients with unexplained mental retardation, the (CGG)n repeats of the FMR1 gene were analyzed by PCR and FragilEase@*RESULTS@#For the 201 patients with unexplained mental retardation, 15 were identified with full mutations of the FMR1 gene. The prevalence of fragile X syndrome (FXS) in patients with unexplained mental retardation was determined as 7.5% (15/201). Prenatal diagnosis was provided for 6 pregnant women with pre- or full mutations. Analysis revealed that women with mental retardation and full FMR1 mutations exhibited a skewed XCI pattern with primary expression of the X chromosome carrying the mutant allele.@*CONCLUSION@#FXS has a high incidence among patients with unexplained mental retardation. Analysis of FMR1 gene (CGG)n repeats in patients with unexplained mental retardation can facilitate genetic counseling and prenatal diagnosis for their families. FMR1 gene (CGG)n repeats screening should be recommended for patients with unexplained mental retardation.

Application of LC-MS/MS in the accurate assessment of vitamins / 中华检验医学杂志

Vitamins are classified as either fat-soluble (vitamins A, D, E, K) or water-soluble (vitamins B and vitamin C). Traditional methods of immunoassay have only been developed for vitamins D,B6, B9 and B12. However, they cannot distinguish between vitamin subtypes such as D2, D3 and associated epi isomers (which has higher leveks in infants),giving false positive or negative results. Mass spectrometry has become a gold standard method for small molecule analysis in biological samples with its advantages in speed,resolution,sensitivity and specificity. It is widely used in clinical research and diagnosis and provides an efficient method for simultaneous detection of multivitamins in one injection using one low volume sample collection.

Identification and analysis of gene mutations of an neurofibromatosis type 1 patient / 中国医师杂志

Objective To explore mutation diagnosis and discuss the pathogenic and clinical characteristics of neurofibromatosis type 1 (NF1).Methods DNA sequencing combined with denaturing highperformance liquid chromatography (DHPLC) method was used to diagnose patients and parents.Results A new nonsense mutations c.503C ＞ G(p.S168 *) was identified.Conclusions NF1 is a rare autosomal dominant genetic disease.Most of them are caused by new mutations.Genetic diagnosis of sporadic cases is very important for treatment and the future generations.

Analysis of FOXL2 gene mutations in 5 families affected with blepharophimosis, ptosis and epicanthus inversus syndrome / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To screen for FOXL2 gene mutations in 6 patients with blepharophimosis, ptosis, and epicanthus inversus syndrome (BPES), and explore their genotype-phenotype correlation.</p><p><b>METHODS</b>Peripheral venous blood samples were collected from the patients for the extraction of genomic DNA. PCR and Sanger sequencing were employed to analyze the coding region and flanking sequences of the FOXL2 gene. Pathogenicity of the identified mutations was verified through literature review and bioinformatic analysis.</p><p><b>RESULTS</b>A heterozygous c.672_701dup30 mutation was found in the probands from the two familial cases, while three heterozygous mutations (two were novel), namely c.462_468del (p.Pro156Argfs*113), c.251T to A (p.Ile84Asn) and c.988_989insG (p.Ala330Glyfs*204) were detected in the three sporadic cases. Literature review and bioinformatic analysis indicated that all these mutations are pathogenic.</p><p><b>CONCLUSION</b>Identification of causative mutations in the BPES patients has provided a basis for genetic counseling and reproductive guidance. The novel mutations have enriched the mutation spectrum of the FOXL2 gene.</p>

Evaluation of performance of five bioinformatics software for the prediction of missense mutations / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To study the prediction performance evaluation with five kinds of bioinformatics software (SIFT, PolyPhen2, MutationTaster, Provean, MutationAssessor).</p><p><b>METHODS</b>From own database for genetic mutations collected over the past five years, Chinese literature database, Human Gene Mutation Database, and dbSNP, 121 missense mutations confirmed by functional studies, and 121 missense mutations suspected to be pathogenic by pedigree analysis were used as positive gold standard, while 242 missense mutations with minor allele frequency (MAF)>5% in dominant hereditary diseases were used as negative gold standard. The selected mutations were predicted with the five software. Based on the results, the performance of the five software was evaluated for their sensitivity, specificity, positive predict value, false positive rate, negative predict value, false negative rate, false discovery rate, accuracy, and receiver operating characteristic curve (ROC).</p><p><b>RESULTS</b>In terms of sensitivity, negative predictive value and false negative rate, the rank was MutationTaster, PolyPhen2, Provean, SIFT, and MutationAssessor. For specificity and false positive rate, the rank was MutationTaster, Provean, MutationAssessor, SIFT, and PolyPhen2. For positive predict value and false discovery rate, the rank was MutationTaster, Provean, MutationAssessor, PolyPhen2, and SIFT. For area under the ROC curve (AUC) and accuracy, the rank was MutationTaster, Provean, PolyPhen2, MutationAssessor, and SIFT.</p><p><b>CONCLUSION</b>The prediction performance of software may be different when using different parameters. Among the five software, MutationTaster has the best prediction performance.</p>

Paramyotonia congenita caused by a novel mutation of SCN4A gene in a Chinese family / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To detect SCN4A gene mutation in a pedigree with paramyotonia congenita in order to facilitate genetic counseling and assisted reproduction.</p><p><b>METHODS</b>Clinical data of the family was collected. DNA was extracted from peripheral blood samples. Potential mutation of the SCN4A gene was screened using PCR-Sanger sequencing. Potential mutation was detected in 3 affected relatives, 4 unaffected relatives and 100 unrelated healthy controls. Bioinformatics software was used to predict the effect of mutation on the protein function and conservation of the sequence at the mutation site across various species.</p><p><b>RESULTS</b>A novel missense mutation c.4427T>C (p.Met1476Thr) was detected in the exon 24 of the SCN4A gene in the proband and other 3 affected relatives, but not in 4 unaffected relatives and 100 unrelated controls. Bioinformatic analysis indicated that the codon is highly conserved across various species, and that the mutation has caused damage to the structure and function of SCN4A protein.</p><p><b>CONCLUSION</b>The c.4427 T>C (p.Met1476Thr) mutation of the SCN4A gene may contribute to the paramyotonia congenita. Detection of SCN4A gene mutation is an effective method for the diagnosis of paramyotonic congenita.</p>

Common mutations of congenital adrenal hyperplasia are also the hotspots for new mutations / 南方医科大学学报

<p><b>OBJECTIVE</b>To discuss the genetic diagnosis of congenital adrenal hyperplasia (CAH) and investigate the resource of gene mutations in CAH.</p><p><b>METHOD</b>Enzymatic methods with restriction endonucleases that specifically recognized the mutation sites were used to detect the gene mutations in patients with CAH and their relatives. Polymerase chain reaction and direct sequencing were used to identify the mutations in 21-hydroxylase gene, and short tandem repeat (STR) typing was used to determine the sources of the mutations.</p><p><b>RESULTS</b>One CAH patient had two known mutations in 21-hydroxylase gene, namely the I2g and I172N mutations. The former mutation was inherited from the biological mother and the latter was not inherited.</p><p><b>CONCLUSION</b>The 9 common mutations of CAH are also the hotspots for new mutations.</p>

Chemical constituents of Desmodium sambuense / 中国中药杂志

The chemical constituents of Desmodium sambuense were studied. Chromatographic techniques were applied to isolate and purify the constituents, and the structures were identified on the basis of physico-chemical and spectroscopeic methods. Thirteen compounds were isolated from the 75% ethanol extract of Desmodium sambuens and elucidated as beta-amyrin(1), betulic acid(2), daucosterol(3), triacontanoic acid(4), lup-20(29)-en-3-one(5), tetracosanoic-2,3-dihydroxypropylester(6), stigmast-5-ene-3beta, 7alpha-ol (7),methyl phaeophorbidea(8), o-hydroxy benzoic acid(9),beta-sitosterol(10),d-catechin(11), luteolin (12), epigallocatechin (13). All of the compounds were isolated from this plant for the first time.

Chemical constituents and bioactivity of Teucrium pilosum / 中国中药杂志

<p><b>OBJECTIVE</b>To study the chemical constituents and bioactivity of Teurium pilosum.</p><p><b>METHOD</b>Various column chromatographic techniques were used to isolate the constituents. A combination of EI-MS, NMR spectroscopy and X-Ray were applied to identify the structures. The anti-microorganism was accomplished by disk diffusion method, the antioxidant activity was assayed by the DPPH microanalysis models and the inhibitory activity of alpha-glucosidase was screened In vitro.</p><p><b>RESULT</b>Eight compounds were isolated and identified as: glyceryl tristearate (1), 2,5-dioxolanone (2), fernenol (3), stigmasta-5,22-dien-3P-ol (4), 24-nor cholesta-5,22 (E)-dien-3beta-ol (5), ca-spinasterol (6), (3,4-dihydroxyphenyl) acrylate (7), 3,4-dihydroxy phenyl acrylic acid (8).</p><p><b>CONCLUSION</b>All compounds have been isolated from the genus for the first time. Compound 3 [IC50 = (37.63 +/- 3.45) mg +/- L(-1)], 6 [IC50 = (178.92 +/- 4.99) mg x L(-1)] and 8 [IC50 = (44.32 +/- 7.02) mg x L(-1)] are of higher inhibitory alpha-glucosidase activity than that of acarbose [IC50 = (1081.27 +/- 12.3) mg x L(-1)]. Compound7 [IC50 = (4.81 +/- 0.96) mg x L(-1)] and 8 [IC50 = (4.16 +/- 0.11) mg L(-1)] showed higher antioxidant activity than that of BHT [IC50 = (35.64 +/- 0.36) mg x L(-1)] and BHA [IC50 = (8.74 +/- 0.39) mg x L(-1)]. Compound 5-8 exhibited inhibitory activity against Fusarium graminearum. Compound 5 and 8 showed inhibitory activity against Botrytis cinerea.</p>