Objective: To explore the genotype-phenotype relationship of Wilson\'s disease (WD) and further study the mutation spectrum in the ATP7B gene. Methods: The clinical data and genetic test results of 115 cases with WD diagnosed in the First Affiliated Hospital of Zhengzhou University from 2015 to 2022 were retrospectively analyzed. The rank sum test was used for quantitative data comparison, and χ(2) test was used for count data comparison. Multivariate logistic regression was used to analyze the relationship between patients\' genotype and phenotype. Results: The onset of liver manifestations (hepatic type) accounted for 60.9%, neurological symptoms (cerebral type) for 13.0%, and mixed hepato-cerebral symptoms for 26.1%. Presymptomatic individuals (hepatic types) accounted for 62.9%. Next-generation sequencing- diagnosed WD cases accounted for 87.8%. Combined multiplex ligation-dependent probe amplification assay-diagnosed WD cases accounted for 89.6%. A single case with a detected pathogenic locus accounted for 10.4%. The diagnostic rate of WD by genetic testing combined with clinical data was 100%. A total of 76 ATP7B mutations were detected, and the top three mutation frequencies were c.2333G>T (p.Arg778Leu) (30.7%), c.2975C>T (p.Pro992Leu) (7.3%), and c.2621C>T (p.Ala874Val) (6.4%). The mutations were mainly distributed in exons 8, 11-13, and 15-18, accounting for more than 90% of the total mutations. Eight new mutations were found, including c.3724G>A (p.Glu1242Lys), c.3703G>C (p.Gly1235Arg), c.3593T>C (p.Val1198Ala), c.2494A>C (p.Lys832Gln), c.1517T>A (p.Ile506Lys), c.484G>T (p.Glu162Ter), c.1870-49A>G, and the missing of exons 10-21. Liver histopathology showed cellular edema, degeneration, inflammation, and necrosis, as well as a 42.8% copper staining positive rate. Genotype-phenotype analysis showed that the p.Arg778Leu mutation had higher alanine aminotransferase (ALT) levels than those carrying other mutations (P=0.024), while the homozygous mutation of p.Arg778Leu was associated with cerebral-type patients (P=0.027). Conclusion: Genetic testing plays an important role in the diagnosis of WD. p.Arg778Leu is the first high-frequency mutation in the Chinese population, and patients carrying it have higher ALT levels. The p.Arg778Leu homozygous mutation is prone to causing cerebral-type WD. This study expands the ATP7B gene mutation spectrum.
目的： 探讨肝豆状核变性（WD）的基因型-表型关系，研究ATP7B基因突变谱。 方法： 回顾性分析2015年至2022年在郑州大学第一附属医院确诊的115例WD患者的临床资料和基因检测结果。计量资料比较采用秩和检验，计数资料比较采用χ(2)检验；采用多因素logisitc回归法分析患者基因型和表型的相关性。 结果： 以肝脏表现起病的（肝型）占60.9%，神经系统症状起病的（脑型）占13.0%，肝脑混合型占26.1%。症状前个体占肝型的62.9%。二代测序诊断WD的占87.8%，联合多重连接探针扩增技术诊断WD的占89.6%，仅检测到1个致病位点的占10.4%。基因检测结合临床资料对WD的诊断率为100%。共检出ATP7B变异76种，突变频率最高前3位的为c.2333G>T(p.Arg778Leu，30.7%）、c.2975C>T(p.Pro992Leu，7.3%）和c.2621C>T(p.Ala874Val，6.4%）。变异主要分布在第8、11～13和15～18号外显子，占变异总数的90%以上。发现新变异8个，分别为c.3724G > A（p.Glu1242Lys）、c.3703G > C（p.Gly1235Arg）、c.3593T > C（p.Val1198Ala）、c.2494A > C（p.Lys832Gln）、c.1517T > A（p.Ile506Lys）、c.484G > T（p.Glu162Ter）、c.1870-49A > G和第10～21号外显子缺失。肝组织病理学示细胞水肿变性、炎性和坏死，铜染色阳性率仅为42.8%。基因型-表型分析显示，携带p.Arg778Leu变异者比携带其他变异者的丙氨酸转氨酶（ALT）水平更高（P = 0.024），p.Arg778Leu纯合变异和脑型患者相关（P = 0.027）。 结论： 基因检测在WD确诊中发挥重要作用。p.Arg778Leu为中国人群第1高频变异，携带该变异的患者ALT水平较高；p.Arg778Leu纯合变异易导致脑型WD。该研究扩展了ATP7B基因变异谱。.

BACKGROUND: GATA1-related cytopenia (GRC) is characterized by thrombocytopaenia and/or anaemia ranging from mild to severe. Haematopoietic stem cell transplantation (HSCT) is a healing therapeutic choice for GRC patients. We identified a novel pathogenic variant (GATA1: c.1019delG) in a boy with GATA1-related cytopenia. Then we performed preimplantation genetic testing (PGT) in this GRC family. After a mosaic embryo transfered, a healthy and HLA-compatible with the proband baby was delivered.
METHODS: The proband is a 6-year-old boy who was diagnosed to have transfusion-dependent anaemia since 3 year old. Whole-exome sequencing (WES) showed that the proband has a hemizygous variant c.1019delG in GATA1, which is inherited from his mother. His parents decided to undergo PGT to have a health and HLA-compatible offspring. After whole genome amplification (WGA) of biopsied trophectoderm (TE) cells, next generation sequencing (NGS)-based PGT was preformed to analyse embryos on chromosomal aneuploidy, target mutation and HLA typing. There were 3 embryos HLA-matched to the proband. The genotypes of the 3 embryos were heterozygous variant, hemizygous variant, normal respectively. After a heterozygous, mosaic partial trisomy (chr)16, and HLA-matched embryo transfer, a healthy baby was delivered and whose HSCT is compatible with the proband.
CONCLUSIONS: NGS-based PGT-HLA is a valuable procedure for the treatment of GATA1-related cytopenia caused by GATA1 variants, or other haematological disorders, oncological and immunological diseases. Furthermore, our study reconfirms that mosaic embryos transfer would bring healthy offspring.

OBJECTIVE: To investigate the clinical and genetic features of a child with Dyschromatosis symmetrica hereditaria (DSH) and variant of the ADAR1 gene.
METHODS: A child who was admitted to the Department of Dermatology of the First Affiliated Hospital of Zhengzhou University in June 2020 due to irregular pigmented maculopapular rash on the dorsum of hands was selected as the study subject. Whole exome sequencing (WES) was carried out for the child and his similarly affected father, and Sanger sequencing was used to verify the candidate variant. SWISS-MODEL was used to predict the secondary and tertiary structures of the wild-type and mutant ADAR1 proteins.
RESULTS: The child, a 13-year-old boy, had symmetrical hyperpigmented and depigmented spots on the back of his hands and was clinically diagnosed with DSH. WES and Sanger sequencing results showed that he and his father had both harbored a heterozygous c.2858dup (p.T954Dfs*20) truncating variant in exon 10 of the ADAR1 gene. Based on the guidelines from the American College of Medical Genetics and Genomics, the variant was predicted as pathogenic (PVS1+PM2_Supporting+PM1+PP3).
CONCLUSIONS: The c.2858dup (p.T954Dfs*20) variant of the ADAR1 gene probably underlay the DSH in this pedigree.

OBJECTIVE: To explore the clinical features and genetic basis for a fetus featuring Rhizomelic skeletal dysplasia.
METHODS: A fetus diagnosed at the Reproductive and Genetic Center of Suzhou Municipal Hospital in November 2020 was selected as the study subject. Whole exome sequencing (WES) was carried out for the fetus and its parents. Candidate variants were verified by Sanger sequencing. Peripheral blood smears of both parents were also examined.
RESULTS: The fetus was found to have a small chest and short limbs, which had suggested skeletal dysplasia. Genetic testing revealed that the fetus has harbored compound heterozygous variants of the LBR gene, including a paternally derived c.1687+1G>A and a maternally derived c.1757G>A (p.Arg586His). The blood smear of the father showed Pelger-Huet anomaly with hyposegmentation of neutrophil nuclei, while the neutrophils of the mother appeared to be normal. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG) and the Association for Molecular Pathology (AMP), the c.1757G>A (p.Arg586His) variant was classified as likely pathogenic (PM3_Strong+PM2_Supporting+PP3), and so was the c.1687+1G>A variant (PVS1-Moderate+PM3+PM2-Supporting+PP4).
CONCLUSIONS: The compound heterozygous variants of the LBR gene probably underlay the pathogenesis of skeletal dysplasia in this fetus.

OBJECTIVE: To explore the clinical phenotype and genetic basis of a child with Neutral lipid storage disease with myopathy (NLSDM).
METHODS: A child who was admitted to the First Affiliated Hospital of Zhengzhou University in February 2021 for a history of elevated creatine kinase (CK) for over 2 months was selected as the study subject. Clinical and laboratory examinations were carried out, and the child was subjected to whole exome sequencing. Candidate variants were validated by Sanger sequencing of her family members.
RESULTS: The patient, a 9-year-old female, had exhibited weakness in the lower limbs, elevated CK level, and refractory cardiomyotrophy. Genetic testing revealed that she has harbored c.32C>G (p.S11W) and c.516C>G (p.N172K) compound heterozygous variants of the PNPLA2 gene, which were respectively inherited from her mother and father. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), both variants were rated as likely pathogenic (PM1+PM2_Supporting+PP3+PP4).
CONCLUSIONS: The c.32C>G (p.S11W) and c.516C>G (p.N172K) compound heterozygous variants of the PNPLA2 gene probably underlay the myasthenia gravis and elevated creatine kinase in this child.

OBJECTIVE: To explore the clinical features and genetic etiology of a Chinese pedigree affected with Cowden syndrome (CS).
METHODS: A CS pedigree diagnosed in November 2022 at the Ningde Municipal Hospital Affiliated to Ningde Normal University was selected as the study subject. Clinical data were collected, and genetic testing was carried out for available members. Pathogenicity analysis was carried out for the candidate variant.
RESULTS: The proband, a 7-year-old male, was found to have autism and intellectual disability. Whole exome sequencing revealed that he has harbored a c.462_463del (p.F154Lfs25) variant of the PTEN gene. The proband\'s 35-year-old mother, who was diagnosed with pulmonary hamartomas at our hospital, has manifested with lipomas, nodular goiter, and adenomas. Sanger sequencing confirmed that she was also heterozygous for the c.462_463del (p.F154Lfs25) variant of the PTEN gene. No other family members has carried the same variant. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the variant was classified as pathogenic (PVS1+PM2_Supporting+PM6).
CONCLUSIONS: The newly discovered c.462_463del (p.F154Lfs*25) variant of the PTEN gene probably underlay the CS in this pedigree. CS patients have higher risk for developing malignant tumors. Clinicians should be aware of this condition and emphasize follow-up of the patients.

OBJECTIVE: To explore the genetic basis for a child featuring facial dysmorphism and intellectual disabilities.
METHODS: A child who was diagnosed at Linyi People\'s Hospital on January 5 2023 due to \"mental retardation\" was selected as the study subject. Peripheral blood samples of the child and his parents, in addition with an amniotic fluid sample from the his mother were collected for the extraction of genomic DNA. Whole exome sequencing was carried out for the child, and candidate variant was verified by Sanger sequencing of his family members.
RESULTS: The child was found to harbor a hemizygous c.1123dupG (p.E375Gfs*4) variant of the NEXMIF gene, for which both of his parents and the fetus were of the wild type. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the variant was predicted to be pathogenic (PVS1+PS2-P+PM2-P). A healthy infant was subsequently born.
CONCLUSIONS: The hemizygous c.1123dupG (p.E375Gfs*4) variant of the NEXMIF gene probably underlay the disease in this child. Based on his clinical phenotype and genotype, the child was ultimately diagnosed with X-linked intellectual developmental disorder-98. Above finding has also enriched the mutational spectrum of the NEXMIF gene.

OBJECTIVE: To explore the clinical features and genetic basis for a child with Intellectual developmental disorder (IDD) and epilepsy.
METHODS: A child who was admitted to the Children\'s Medical Center of the Affiliated Hospital of Guangdong Medical University in February 2021 was selected as the study subject. Clinical data of the child was collected. Peripheral blood samples of the child and her parents were collected and subjected to whole exome sequencing (WES). Candidate variant was verified by Sanger sequencing.
RESULTS: The patient, a 3-month-and-27-day female infant, had developed the symptoms in the neonatal period, which included severe developmental delay, respiratory difficulties and pauses, increased muscle tone of four limbs, feeding difficulty, and seizures. Cerebral MRI revealed bilateral cerebellar hypoplasia, and video EEG showed slightly increased sharp waves emanating predominantly from the right parietal, occipital, and posterior temporal regions. WES revealed that she has harbored a missense c.3196G>A (p.Glu1066Lys) variant of the CLTC gene, which was confirmed to be de novo by Sanger sequencing. Based on the guideline from the American College of Medical Genetics and Genomics (ACMG), the variant was classified as likely pathogenic (PS2+PM2_Supporting+PP3).
CONCLUSIONS: The c.3196G>A (p.Glu1066Lys) missense variant of the CLTC gene probably underlay the pathogenesis in this child. Above finding has facilitated her diagnosis and treatment.

OBJECTIVE: To explore the clinical and genetic characteristics of two newborns with Central nuclear myopathy (CNM).
METHODS: Two newborns with CNM diagnosed clinically at Wuhan Children\'s Hospital Affiliated to Tongji Medical College, Huazhong University of Science and Technology in April 2019 and November 2021 were selected as the study subjects, and their clinical data was collected. Both newborns and their parents were subjected chromosomal karyotyping analysis and whole exome sequencing (WES). Candidate variants were verified by Sanger sequencing. Pathogenicity of the candidate variants was evaluated based on the guidelines from the American College of Medical Genetics and Genomics (ACMG).
RESULTS: Patient 1 was a male neonate and Patient 2 was a 20-day-old male infant. Both newborns had featured difficulty in breathing and swallowing. WES revealed that both had harbored hemizygous variants of the MTM1 gene, which were verified by Sanger sequencing. Patient 1 had harbored a c.1261A>G variant. Based on the ACMG guidelines, it was rated as pathogenic (PVS1+PM2_Supporting+PP3). Patient 2 harbored a c.342delT variant, which was also rated as pathogenic (PVS1+PM2_Supporting+PP3).
CONCLUSIONS: The c.1261A>G and c.342delT variants of the MTM1 gene probably underlay the pathogenesis of CNM in the two patients.

OBJECTIVE: To explore the clinical characteristics and molecular basis for children and adolescents with monogenic diabetes.
METHODS: A retrospective analysis was carried out for the clinical manifestations and laboratory data of 116 children and adolescents diagnosed with diabetes at Ningbo Women and Children\'s Hospital from January 2020 to March 2023. Whole exome sequencing and mitochondrial gene sequencing were carried out on 21 children with suspected monogenic diabetes.
RESULTS: A total of 10 cases of monogenic diabetes were diagnosed, all of which were Maturity-onset Diabetes Of the Young (MODY). Six cases of MODY2 were due to GCK gene mutations, 1 case of MODY3 was due to HNF1A gene mutation, 2 cases of MODY12 were due to ABCC8 gene mutations, and 1 case of MODY13 was due to KCNJ11 gene mutation. Nine of the 10 patients with MODY had no typical symptoms of diabetes. A family history of diabetes was significantly more common in the MODY group compared with the T1DM and T2DM groups (P < 0.05). The BMI of the MODY group was higher than that of the T1DM group (P < 0.05). The initial blood glucose level was lower than that of the T1DM group (P < 0.05), and there was no significant difference compared with the T2DM group. The fasting C-peptide level of the MODY group was higher than that of the T1DM group (P < 0.05), and there was no significant difference compared with the T2DM group. Glycosylated hemoglobin of the MODY group was lower than both the T1DM and T2DM groups (P < 0.05).
CONCLUSIONS: In this study, MODY has accounted for the majority of monogenic diabetes among children and adolescents, and the common mutations were those of the GCK gene in association with MODY2. Blood glucose and glycosylated hemoglobin of children with MODY were slightly increased, whilst the islet cell function had remained, and the clinical manifestations and laboratory tests had overlapped with those of type 2 diabetes. WES and mitochondrial gene sequencing can clarify the etiology of monogenic diabetes and facilitate precise treatment.