Cytopenia: a report of haplo-cord transplantation in twin brothers caused by a novel germline GATA1 mutation and family survey.

Cytopenia due to the abnormal regulation of GATA1 could manifest as varying degrees of thrombocytopenia and/or anemia and more severely in male children than in female children. Here, we describe the case of pancytopenic and transfusion-dependent twin brothers at our center whose bone marrow puncture revealed low bone marrow hyperplasia. Whole-exome sequencing revealed that the twins had a new germline GATA1 mutation (nm_002049: exon 3:c.515 T >C:p.F172S), which confirmed the diagnosis of GATA1 mutation-related pancytopenia. The mutation was inherited from their mother, who was heterozygous for the mutation. Sanger sequencing verified the pathogenicity of the mutation. Further family morbidity survey confirmed that GATA1 mutation-related pancytopenia is an X-linked recessive genetic disorder. We developed haploid hematopoietic stem cell transplantation programs for twins, with the father as the only donor, and finally, the hematopoietic reconstruction was successful. Although they experienced acute graft-versus-host disease, hemorrhagic cystitis, and a viral infection in the early stage, no abnormal manifestations or transplant-related complications were observed 3 months after transplantation. Through hematopoietic stem cell transplantation technology for one donor and two receptors, we eventually cured the twins. The p.F172S variant in the new germline GATA1 mutation may play an essential role in the pathogenesis of GATA1 mutation-related cytopenia.

Case Report: Eosinophilic gastritis with pyloric stenosis in immune dysregulation, polyendocrinopathy, enteropathy, X-linked syndrome.

Immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome is a rare X-linked recessive immunodeficiency caused by mutations in the forkhead box protein 3 (FOXP3) gene. IPEX is characterized by the onset of intractable diarrhea, type 1 diabetes mellitus (T1DM), and eczema in the early stages of life. The typical clinic triad for IPEX is not always seen. Here, we report a 15-year-old male patient with atypical IPEX syndrome complicated with severe eosinophilic gastritis (EG) and pyloric stenosis. The patient had noticeable eczema during the first year of life and had a history of food allergies. At the age of 3 years, the patient was diagnosed with EG, Helicobacter pylori (HP) infection, pyloric stenosis with recurrent vomiting, and failure to thrive. The patient did not respond to long-term symptomatic treatments in the following years, including methylprednisolone, proton pump inhibitors (PPI), L-glutamine and sodium gualenate granules, anti-HP therapy, and balloon dilation. At the age of 12 years, the patient received surgical interventions, including a laparoscopic jejunostomy feeding tube placement, gastrojejunal anastomosis bypass, and jejunal-jejunal end-to-side anastomosis. Intractable diarrhea and T1DM were not present in the patient. At the age of 14 years, the patient was diagnosed with IPEX syndrome due to a c.748-750del (p.Lys250del) mutation in the leucine zipper domain of the FOXP3 protein. The patient underwent matched sibling peripheral blood hematopoietic stem cell transplantation (HSCT) and showed good evolution after 3 months of HSCT. In summary, this case report provides information of unusual gastrointestinal findings in IPEX syndrome and highlights the need for increased awareness and early diagnosis of IPEX syndrome, which is vital for improving the patient's outcome.

Allogeneic Hematopoietic Stem Cell Transplantation for PEX1-Related Zellweger Spectrum Disorder: A Case Report and Literature Review.

Zellweger spectrum disorder (ZSD) is a heterogeneous group of autosomal recessive disorders characterized by a defect in peroxisome formation and attributable to mutations in the PEX gene family. Patients with ZSD have profound neurologic impairments, including seizures, severe retardation, and dysmorphic features, and poor prognosis. Currently, there is no specific, effective treatment. Here, we investigated the effects of allogeneic hematopoietic stem cell transplantation (allo-HSCT) on PEX1-related ZSD. The suspected clinical proband was first diagnosed at the Department of Neurology of our hospital. The proband died soon after diagnosis, and his family was studied. We found that a brother had the same genetic alterations, and he was diagnosed with Infantile Refsum disease (IRD) as the mildest form of ZSD. We implemented treatment with allo-HSCT, at the request of the child's parents. After transplantation, we observed significant improvements in the clinical manifestations, very-long-chain fatty acids, and brain MRI. The patient has recovered well and not showed any abnormal clinical manifestations after 2 years of follow-up. We have achieved satisfactory short-term results in the treatment of ZSD-IRD with allo-HSCT. Long-term follow-up and observation will be performed to determine the long-term prognosis.

Case Report: A Novel Compound Heterozygous Mutation in IL-10RA in a Chinese Child With Very Early-Onset Inflammatory Bowel Disease.

Very early-onset inflammatory bowel disease (VEO-IBD) is defined as IBD diagnosed in children younger than 6 years of age. VEO-IBD is often associated with a monogenic etiology or primary immune deficiency. Here, we report the case of a 7-month-old Chinese girl diagnosed with VEO-IBD who had a variant in the interleukin-10 receptor A (IL-10-RA) gene. The patient presented with recurrent fevers, abdominal pain, diarrhea, perianal abscesses, and oral ulcers. Whole-exome sequencing (WES) identified a novel compound heterozygote mutation, c.395T>G (p.Leu132Arg)/ex.1del (p.?), in the IL-10RA gene of the patient. The missense mutation c.395T>G (p.Leu132Arg) was inherited from her mother, and ex.1del (p.?) was inherited from her father. Neither mutation has been reported previously. The IL-10RA function of the patient was defective, as demonstrated by a failure of signal transducer and activator of transcription 3 (STAT3) activation in peripheral blood mononuclear cells (PBMCs) stimulated with recombinant IL-10. The patient underwent matched unrelated peripheral blood hematopoietic stem cell transplantation (HSCT), and the clinical manifestations were dramatically improved. In summary, we identified a novel compound heterozygote mutation, c.395T>G (p.Leu132Arg)/ex.1del (p.?), in IL-10RA that caused VEO-IBD in a Chinese child, which further expands the mutational spectrum of IL-10RA.

Generation and characterization of an iPSC line (SHCMDLi001-A) from a 12-year-old Chinese Han patient with TRAF7 syndrome and of an iPSC line (SHCMDLi002-A) from a control individual.

Mutations in TRAF7 cause developmental delay and cardiac, facial, digital anomalies. c.1964G > A variant was most recurrent, suggesting its essentiality of pathogenicity. Further studies to determine the underlying mechanism of c.1964G > A variant are warranted. But no patient-specific cellular models have been generated. Here, we generated an iPSC line with c.1964G > A variant (SHCMDLi001-A) and a line from healthy individual (SHCMDLi002-A). Characterization of SHCMDLi001-A and SHCMDLi002-A demonstrated these iPSCs are free of exogenous reprogramming genes, expressed pluripotency markers, exhibited a normal karyotype and were potential of three germ layer differentiation. These lines provide a valuable resource for studying disease-causing mechanism of TRAF7 variant.

Spectrum of RB1 Germline Mutations and Clinical Features in Unrelated Chinese Patients With Retinoblastoma.

Retinoblastoma (Rb) is a primary intraocular malignant tumor that occurs primarily in children, and results from loss-of-function mutations in the RB transcriptional corepressor 1 (RB1) gene. Genetic testing forms the basis of genetic counseling for affected families, as well as for clinical management of this disease. The aim of this study was to identify germline RB1 mutations and correlate the identified mutations with the clinical features of Rb patients. Genomic DNA was isolated from peripheral blood of 180 unrelated Rb patients and their parents (118 unilaterally and 62 bilaterally affected probands). Mutations in the RB1 gene, including the promoter region and exons 1-27 with flanking intronic sequences, were identified by Sanger sequencing. The samples with negative sequencing results were further subjected to methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) to detect gross deletions or duplications. Sixty-three distinct mutations were identified in 75 of the 180 (41.7%) probands. Of the 75 patients carrying RB1 mutations, 56 developed bilateral Rb, while 19 developed unilateral Rb. The total detection rates for bilateral and unilateral Rb were 90.3% (56/62) and 16.1% (19/118), respectively. Among the 75 patients, the spectrum of mutation types comprised 29.3% (22/75) nonsense mutations, 22.7% (17/75) splicing mutations, 17.3% (13/75) small insertions/deletions, 16.0% (12/75) large deletions/duplications, and 13.3% (10/75) missense mutations, while only 1% (1/75) of the mutations were in the promoter region of the RB1 gene. Age at diagnosis was significantly different (p < 0.01) between patients with positive and negative test results for germline RB1 mutations. A c.2359C > T mutation (p.R787X) was identified in identical twins, but one child was affected bilaterally and the other unilaterally. Of the five patients with deletion of the entire RB1 gene, the deletion of two patients was inherited from unaffected parents. In conclusion, in this study, we provide a comprehensive spectrum of RB1 germline mutations in Chinese Rb patients, and describe the correlations among RB1 mutations, age at diagnosis, and laterality; moreover, we report that the clinical features of individuals carrying an identical mutation in the RB1 gene were highly variable, indicating that the pathogenesis of Rb is more complicated than currently believed.

A de novo MAPRE2 variant in a patient with congenital symmetric circumferential skin creases type 2.

BACKGROUND: Congenital symmetric circumferential skin creases (CSCSC) was initially described five decades ago. Exome sequencing has recently revealed the genetic etiology of CSCSC. Pathogenic variants in TUBB (OMIM# 191130) and MAPRE2 (OMIM# 605789) have been linked to CSCSC1 (OMIM# 156610) and CSCSC2 (OMIM# 616734), respectively, in an autosomal dominant manner. Four pathogenic variants in MAPRE2 have been previously reported to be associated with CSCSC2. METHODS: Whole-exome sequencing (WES) has been performed and an in-house pipeline was used to conduct a phenotype-driven data analysis. All candidate variants were confirmed by Sanger sequencing. RESULTS: Here we report a 2-year-old boy characterized by absent expressive speech, normal to mild over growth, facial dysmorphic features, remarkable circumferential skin creases on both forearms and ankles. WES disclosed a de novo missense MAPRE2 variant, c.518G>A (p.Arg173Gln), as the molecular cause of this complex phenotype. We described detailed clinical characterization of this patient and compared the available clinical data of individuals with MAPRE2 variants to demonstrate the phenotypic spectrum. CONCLUSION: Our study reports the first patient of Asian origin with CSCSC2 due to a pathogenic mutation of MAPRE2 and expands the clinical and genetic spectrum of CSCSC2.

[Mutation analysis of two pedigrees with suspected oculocutaneous albinism].

OBJECTIVE: To analyze the clinical presentation and gene of 2 pedigrees with suspected oculocutaneous albinism(OCA), and provide basis for clinical classification, genetic counseling and prenatal diagnosis. METHODS: Variants were identified using next-generation sequencing(NGS) and confirmed by Sanger sequencing in 2 pedigrees with suspected OCA. The pathogenicity of the variants was analyzed according to the American College of Medical Genetics and Genomics (ACMG) standard. RESULTS: Two compound heterozygous mutations of TYR and OCA2 genes were identified respectively in 2 pedigrees with suspected OCA. The mutation of c.819+3insATATGCC in TYR and the mutation of c.1870G>C in OCA2 are first reported in this study. The pathogenicity analysis shows that two novel mutations are likely pathogenic by combination of prediction of SIFT, Polyphen-2 and Human Splicing Finder. CONCLUSION: The findings of this study expand the mutational spectrum of OCA. Compound heterozygous mutations in the TYR and OCA2 gene may be responsible for clinical manifestations of 2 pedigrees with suspected OCA.