OBJECTIVE: To explore the clinical phenotype and genetic etiology of a neonate with X-linked alpha-thalassemia mental retardation syndrome (ATR-X) caused by ATRX gene variant, and review related literature on children with ATR-X caused by ATRX gene variants. METHODS: A case of ATR-X neonate who was transferred to the First Affiliated Hospital of Zhengzhou University on February 11, 2022 for poor effect of treatment in the neonatology department of the hospital where he was born for 4 days due to "postnatal slow response, groaning, and cyanosis of the skin for 30 min" was selected as the study subject. 3 mL of peripheral blood was collected from the child and their parents, and genomic DNA was extracted for whole exome sequencing (WES). Sanger sequencing was used to verify the pathogenic gene variations in the child's family. The pathogenicity of genetic variant sites was assessed based on the Standards and Guidelines for the Interpretation of Sequence Variants by American College of Medical Genetics and Genomics (ACMG). The amino acid sequence conservation analysis of relevant variant proteins was conducted by the Universal Protein Resource Database (UniProt) and visual analysis of these variant proteins was performed by Swiss online protein three-dimensional modeling database (SWISS-MODEL). Using keywords such as "ATRX gene" and " X-linked alpha-thalassemia mental retardation syndrome" both in Chinese and English, relevant literature on ATR-X children caused by ATRX gene variants was retrieved from the CNKI, Wanfang Data Knowledge Service Platform, and PubMed databases, and the clinical phenotypes of ATR-X patients reported in the retrieved literature were analyzed. The literature retrieval time was set from the establishment of each database to December 31st, 2023. This study followed the research procedures approved by the Ethics Committee of the First Affiliated Hospital of Zhengzhou University (Ethics No. 2023-KY-1360-002), and informed consent of clinical study was signed by the guardian of the child. RESULTS: The child in this study presented with symptoms such as delayed response, feeding difficulties accompanied by vomiting, low body temperature, hypotonia in all extremities, apnea, abnormal hearing screening, and a Neonatal Behavioral Neurological Assessment (NBNA) score of 19 (lower than the normal range).Hemoglobin (Hb) electrophoresis suggested the presence of α-thalassemia. The results of WES and Sanger sequencing revealed a hemizygous missense variant c.668G>A (p.C223Y) in exon 9 of the ATRX gene in the child of the study, neither of the parents of the child carried this variant, indicating that it is a de novo variant. Based on the Standards and Guidelines for the Interpretation of Sequence Variants released by ACMG, this gene variant was assessed as pathogenic (PS2+PM2_Supporting+PP3_Strong+PP4_Strong). The results of amino acid sequence analysis revealed that the pathogenic variant site normally encodes cysteine, which is highly conserved among various animal species. This pathogenic variant can lead to alterations in the hydrogen bonding structure of ATRX protein, thereby affecting its structural stability. Based on the clinical manifestations and genetic testing results of the child in this study, a diagnosis of ATR-X syndrome was established Based on the literature retrieval strategy established in this study, 13 relevant articles concerning ATR-X syndrome in children caused by ATRX gene variants were retrieved, including 5 Chinese articles and 8 English articles, involving a total of 311 ATR-X children. Including the child in this study, the total number of ATR-X children reaches 312. All 312 children were male and presented with mental retardation. Among them, 45.8% (143/312) had coexisting α-thalassemia, 45.2% (141/312) had abnormal genital appearance, 44.2% (138/312) had facial malformations, and 30.8% (96/312) had hypotonia. Other phenotypes included microcephaly, skeletal dysplasia, among others. CONCLUSION The ATR-X child in this study exhibit a range of clinical phenotypes, including delayed growth and development, facial malformation, abnormal genital appearance, apnea, vomiting symptoms, among others. The de novo variant of ATRX gene c.668G>A (p.C223Y) was identified as the genetic etiology. This study contributes to the expansion of the clinical phenotype spectrum and genetic variation spectrum of ATR-X children.
Humans ; X-linked Nuclear Protein/genetics* ; alpha-Thalassemia/genetics* ; X-Linked Intellectual Disability/genetics* ; Male ; Infant, Newborn ; Exome Sequencing ; Mutation

OBJECTIVE: To investigate the clinical phenotypic and genetic characteristics of three children with Paroxysmal kinesigenic dyskinesia (PKD) and Self-limited familial infantile epilepsy (SeLIE) caused by PRRT2 gene mutation. METHODS: Three children with PKD and SeLIE caused by PRRT2 gene mutation (children 1-3) who were treated in the First Affiliated Hospital of Zhengzhou University from November 2022 to August 2023 were selected as the research subjects. A retrospective study was conducted to collect the clinical and family history data of the three children. 2 mL of peripheral venous blood from children 1-3 and parents of children 1-2 were collected (parents of children refused to undergo genetic testing and no blood samples were collected), genomic DNA was extracted, whole exome sequencing (WES) was performed, and Sanger sequencing method was used for verification. According to the Classification Standards and Guidelines for Genetic Variants formulated by the American Society of Medical Genetics and Genomics (ACMG) (hereinafter referred to as the "ACMG Guidelines"), the pathogenicity of the variant loci detected in three children was rated, and the detrimental loci of the variant loci were analyzed by multiple bioinformatics software. This study has been approved by the Ethics Committee of the First Affiliated Hospital of Zhengzhou University (Ethics No. 2024-KY-0881-002). RESULTS: The clinical data and genetic test results of the three children in this study are as follows. Child 1: female, age of onset of 4 months and 10 days, with seizures, manifested as sudden cessation of movements, staring in both eyes, cyanosis of the lips, paleness, and stiffness and shaking of limbs. The results of genetic testing showed that child 1 had maternal PRRT2 gene c.583_584dup (p.P196Afs*34) frameshift variant, which was rated as a pathogenic variant (PVS1 PM2_Supporting PP4) according to ACMG guidelines. According to the clinical manifestations and genetic test results of child 1, he was diagnosed with SeLIE and took oral sodium valproate [0.5 mL/(kg.d)], and was still taking medication at the follow-up of 2 years old, and did not have seizures again after 5 months of age. Child 2: male, age of onset of 10 years old, manifested as dystonia after sudden movement. The results of genetic testing showed that child 2 had PRRT2 gene mutations: paternal c.649dupC (p.R217Pfs*8) frameshift variant and maternal c.445C>A (p.Q149K) mutation. Among them, c.649dupC was a reported pathogenic variant, and according to ACMG guidelines, c.445C>A variant was rated as a variant of unknown clinical significance (PM2_Supporting), with a high probability of benignness. According to the clinical manifestations and genetic test results of the child 2, he was diagnosed with PKD, and was followed up with oral oxcarbazepine 9 mg/(kg.d) until 12 years and 2 months, and was still on the drug, and there was no recurrence of the seizure of the form of dyskinesia after taking the drug. Child 3: male, age of onset of 11 years old, manifested by dystonia after sudden exercise. The results of genetic testing showed that child 3 had a missense variant of PRRT2 gene c.904G>C (p.D302H), and his parents refused genetic testing, and the source of the mutation was unknown, and the variant was rated as a variant of unknown clinical significance (PM2_Supporting+PP3_Moderate+PP4) according to ACMG guidelines. According to the clinical manifestations and genetic test results of child 3, he was diagnosed with PKD, and was treated with oral oxcarbazepine 10 mg/(kg.d) for 1 year and then discontinued on his own, and was followed up at the age of 17, and there was no recurrence of the seizure of the form of movement disorder after taking the drug. CONCLUSION One case of SeLIE and two cases of PKD caused by PRRT2 gene mutations responded well to anti-seizure drugs. In this study, four variant loci of PRRT2 gene were found: c.583_584dup, c.904G>C, c.649dupC, c.445C>A, among which c.583_584dup were new variants, enriching the variant spectrum of PRRT2 gene.
Humans ; Male ; Nerve Tissue Proteins/genetics* ; Female ; Membrane Proteins/genetics* ; Mutation ; Child, Preschool ; Infant ; Phenotype ; Dystonia/genetics* ; Retrospective Studies ; Child

OBJECTIVE: To analyze the clinical characteristics and genetic etiology of a child with Christianson syndrome (CS). METHODS: A 1-year-and-5-month-old boy with CS diagnosed at the First Affiliated Hospital of Zhengzhou University in April 2021 was selected as the study subject. Clinical data were retrospectively analyzed. Peripheral blood samples were obtained from the child and his parents, followed by genomic DNA extraction and whole exome sequencing (WES). Candidate variant was validated by Sanger sequencing. This study has been approved by the Medical Ethics Committee of the Hospital of Zhengzhou University (Ethics No. 2024-KY-1103-001). RESULTS: The child has manifested with seizures, microcephaly, and global developmental delay. WES revealed that he has harbored a novel de novo hemizygous nonsense variant of the SLC9A6 gene, namely c.1014G>A (p.W338*). Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the variant was rated as pathogenic. CONCLUSION The hemizygous c.1014G>A nonsense variant of the SLC9A6 gene probably underlay the pathogenesis in this child. Above discovery has expanded mutational spectrum of the SLC9A6 gene and enabled definite diagnosis of the child.
Humans ; Male ; Infant ; Microcephaly/genetics* ; Spasms, Infantile/genetics* ; Sodium-Hydrogen Exchangers/genetics* ; Exome Sequencing ; Intellectual Disability/genetics* ; Genetic Diseases, X-Linked/genetics* ; Mutation ; Seizures/genetics* ; Ataxia ; Epilepsy ; Ocular Motility Disorders

OBJECTIVE: To explore the prevalence and characteristics of chromosomal abnormalities in abortuses during early pregnancy with single nucleotide polymorphism microarray (SNP-array). METHODS: For 520 abortuses, copy number variations (CNVs) in chorionic villi were analyzed with SNP-array. RESULTS: In 510 (98.1%) of the samples, the analysis was successful. Among these, 57.6% (294/510) of the samples were found to harbor clinically significant chromosomal abnormalities. 38.8% of the samples (198/510) had a normal result. 2.4% (12/510) of the samples harbored benign CNVs, and 1.2% (6/510) harbored variants of uncertain significance (VOUS). Aneuploidies, polyploidies, pathogenic CNVs and uniparental disomies (UPD) had accounted for 75.2% (221/294), 13.9% (41/294), 8.2% (24/294), and 2.7% (8/294) of the samples, respectively. 45,XO was the most common finding, which was followed by trisomy 16 and trisomy 22. 69,XXY was the most common polyploidy. CONCLUSION Chromosomal abnormalities are the main cause for early miscarriage, among which aneuploidies are most common. The prevalence of aneuploidies is significantly increased among women over 35. SNP-array analysis has the advantage of high success rate, high resolution and great accuracy, but the clinical significance of microdeletions/microduplications found by SNP-array can be difficult for interpretation.
Chorionic Villi ; Chromosome Aberrations ; Chromosome Disorders ; DNA Copy Number Variations ; Female ; Genetic Testing ; Humans ; Karyotyping ; Polymorphism, Single Nucleotide ; Pregnancy

OBJECTIVETo analyze mutations of IDUA gene in two pedigrees affected with mucopolysaccharidosis type I and provide prenatal diagnosis for them.

METHODSThe 14 exons of the IDUA gene were subjected to PCR amplification and Sanger sequencing.

RESULTSFor pedigree 1, the proband was found to harbor compound heterozygous mutations c.46-57delTCGCTCCTGGCC (p.Ser16_Ala19del) of exon 1 and c.1147delC (p.Arg383Alafs*57) of exon 8 of the IDUA gene, which were inherited from his father and mother, respectively. The latter was unreported previously. Prenatal diagnosis suggested that the fetus has carried a heterozygous c.46-57delTCGCTCCTGGCC mutation. For family 2, the proband was also found to carry compound mutations of the IDUA gene, namely c.721T to C (p.Cys241Arg) of exon 6 and c.1491delG (p.Thr497fs27) of exon 8, which were inherited from her mother and father, respectively. Neither mutation was reported previously. Prenatal diagnosis suggested that the fetus has carried a heterozygous c.721T to C mutation.

CONCLUSIONMutations of the IDUA gene probably underlie the MPS-I in both pedigrees. Above results have enriched the spectrum of IDUA gene mutations and facilitated prenatal diagnosis for both families.

Adult ; Asian Continental Ancestry Group ; genetics ; Base Sequence ; Child ; Child, Preschool ; China ; DNA Mutational Analysis ; Female ; Fetal Diseases ; diagnosis ; genetics ; Heterozygote ; Humans ; Iduronidase ; genetics ; Male ; Molecular Sequence Data ; Mucopolysaccharidosis I ; diagnosis ; embryology ; genetics ; Pedigree ; Pregnancy ; Prenatal Diagnosis ; Sequence Deletion

Three-parent test tube baby technology is important to solve the mitochondrial genetic disease.Once available,it raises greatly ethical controversy such as breaking traditional family values,hitting the religious belief,existing unknown risks,correctly handling the failed embryo,as well as the influence on the social status of the babies.Regarding these controversy,we can discuss it from several aspects.Because the development of ethics is behind the progress of science and technology,we should affirm the value of three-parent test tube baby technology and balance the development of science and technology with respecting the religious beliefs.Strict supervision system and standard application system reflect our respect for life.Incomprehension to the unknown things should become the motivation of our inquiry.We should face up to our fear of three-parent test tube baby technology,and thus to strengthen research and deepen understanding.Based on the above argument,this paper puts forward the ethical principles that should be followed in the development of three-parent test tube baby technology,namely respect,benefit,no harm and justice.

Since CRISPR/Cas9 has been discovered,it opens a new era for gene therapy with its low cast,high efficiency,short cycle,easy operation and other characteristics.In 2015,Huang Junjiu had used the technique to nodify human embryonic cell for the first time,leading to widespread attention at home and abroad.For nearly 50 years,ethical discussion of gene therapy has never stopped.Through reviewing the development of gene therapy,this paper analyzed several key issues of ethical controversy in gene therapy,such as safety,effectiveness,justice,right,interest orientation and so on,and put forward that gene therapy and ethics are not two opposite sides and cannot be treated separately,the development of gene therapy should follow certain ethical norms and technical norms and it should use the bioethical principles to direct gene therapy.

Objective To evaluate the efficacy of non-invasive prenatal screening (NIPS) in the detection of fetal aneuploidies.Methods Cell free DNA was sequenced in 5 566 pregnant women to identify the fetal aneuploidies in the First Affiliated Hospital of Zhengzhou University from January 1st,2015 to March 15th,2016.Among them,5 230 (93.96％,5 230/5 566) were singleton pregnancies and 336 (6.04％,336/5 566) were twin pregnancies.In singleton pregnancies,1 809 (34.59％,1 809/5 230) were women with advanced maternal age,and 3 421 (65.41％,3 421/5 230) were young women.The positive results of NIPS were validated by karyotyping through invasive procedures and neonatal outcomes were followed up by telephone.Results Among the 5 566 women,69 (1.24％,69/5 566) got positive NIPS results,with 66 in singleton pregnancies and 3 in twin pregnancies.Two were monochorionic diamniotic twins and 1 was dichorionic twin pregnancy.The positive predictive value of NIPS for trisomy 21,18 and 13 were 100.0％,90.9％ and 100.0％,and was 55.6％ for sex chromosome aneuploidies.There was no false negative case found during the follow-up.In the advanced maternal age group and young women group,the prevalence rates of fetal chromosomal aneuploidies were 1.11％ (20/1 809) and 0.94％ (32/3 421),respectively.In the young women with soft markers in fetal ultrasound,the prevalence of fetal chromosomal aneuploidies was 1.44％ (7/487),and in serum high risk women,it was 0.94％ (7/747).In women with the serum screening risk with cut-off value,0.89％(9/1 016) had fetal aneuploidies,and the prevalence was 0.77％(9/1 171) in volunteers.There was no statistically significant difference among these groups (P=0.636).Conclusions There is no difference in the detection rate of fetal aneuploidies between high-risk women in serum screening and volunteers in NIPS.NIPS is more suitable as a first line screening test for women without fetal ultrasound abnormalities.It should be used carefully when there is ultrasound abnormalities.

Objective To analyze the mutation of MUT with Sanger sequencing technology to explore the feasibility of its application in prenatal diagnosis.Methods MUT sequencing was performed in 24 pedigrees who had history of isolated methylmalonic acidemia (MMA) babies and came to the First Affiliated Hospital of Zhengzhou University and Newborn Screening Center of Maternal and Child Health Hospital of He'nan Province between October 2012 and June 2015 for genetic counseling.Meanwhile,another 100 cases of normal controls also had their MUT gene sequence analyzed.After confirming the genotype of each pedigree,we collected the villi of nine high-risk fetuses in nine pedigrees whose parents were prepared for prenatal diagnosis.Results Totally,25 kinds of MUT gene mutations were identified among the 24 isolated MMA pedigrees,in which 11 were novel mutations including one nonsense mutation [c.616C＞T(p.Q206X)],six missense mutations [c.613G＞A(p.E205K),c.894T＞G(p.1298N),c.1009T＞C(p.F337L),c.1154G＞T(p.L385W),c.1663G＞A(p.A555T) and c.1675G＞A(p.R559G) and four frame shift mutations [c.626-627insC(p.P209Pfs*2),c.755-756insA(p.H252Qfs*6),c.756-757insA(p.M253Nfs*5) and c.1581-1582insA(p.A528Ifs*4)].None of the above mutations was detected in the controls.Finally,among the nine pedigrees for prenatal diagnosis,two were determined to have normal MUT gene,four were found to be heterozygous mutation carriers of MUT gene and three were confirmed as complex heterozygous or homozygous mutation carriers.Families of fetus who had normal MUT gene or fetuses who were carriers chose to continue the pregnancy,while those who had heterozygous mutation of MUT gene chose termination.The results of follow-up of newborns were consistent with that of prenatal diagnosis.Conclusions We found two novel mutations in MUT gene that might lead to isolated MMA.And Sanger sequencing technology for MUT gene sequencing analysis might effectively avoid the birth of isolated MMA children.

Objective To analyse MMACHC mutations for 45 pedigrees with combined methylmalonic aciduria and homocyctinuria by Sanger sequencing, and to discuss the utility of prenatal genetic diagnosis for these pedigrees.Method Peripheral blood was collected from 45 probands and their parents from 2012-2015 in Genetic Counselling Clinic of the First Affiliated Hospital of Zhengzhou University, and the DNA were extracted from the blood.Then the coding sequence of MMACHC gene was amplified by PCR, and the PCR products were further sequenced to detect mutations for each pedigree.For 12 families, chorionic villus sampling was performed on the pregnant women to make prenatal genetic diagnosis.Result There were 14 distinct mutations detected in the 45 pedigrees, and the most frequent mutations are c.609G>A(W203X),c.658-660delAAG(K220del)and c.80A>G (Q27A).Two of those mutations have not been reported before:one is a splicing site mutation c.81+1G>A;while the other is a missense mutation c.665A>G,p.Y222C.Most mutations were found in exon 4.Among the 12 pedigrees who received prenatal diagnosis, 2 fetuses were normal, 7 fetuses were carriers of heterozygous mutation, and the other 3 fetuses were patients with compound heterozygous mutation or homozygous mutation.The couples whose fetuses were normal or carriers continued the gestation, while the couples whose fetuses were patients decided to terminate the pregnancy.After delivery, the outcome of the fetuses was the same as the prenatal diagnose results.Conclusion Two novel mutations of MMACHC were identified and prenatal genetic diagnosis helps to avoid the delivery of combined methylmalonic aciduria and homocyctinuria patients.