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* Context.--Identification of rare thalassemia variants requires a combination of multiple diagnostic technologies. Objective.--To investigate a new approach of comprehensive analysis of thalassemia alleles based on third-generation sequencing (TGS) for identification of [alpha]- and [beta]-globin gene variants. Design.--Enrolled in this study were 70 suspected carriers of rare thalassemia variants. Routine gap-polymerase chain reaction and DNA sequencing were used to detect rare thalassemia variants, and TGS technology was performed to identify [alpha]- and [beta]-globin gene variants. Results.--Twenty-three cases that carried rare variants in [alpha]- and [beta]-globin genes were identified by the routine detection methods. TGS technology yielded a 7.14% (5 of 70) increment of rare [alpha]- and [beta]-globin gene variants as compared with the routine methods. Among them, the rare deletional genotype of-THAI was the most common variant. In addition, rare variants of CD15 (G>A) (HBA2:c.46G>A), CD117/118(+TCA) (HBA1:c.354_355insTCA), and [beta]-thalassemia 3.5-kilobase gene deletion were first identified in Fujian Province, China; to the best of our knowledge, this is the second report in the Chinese population. Moreover, HBA1:c.-24C>G, IVS-II-55 (G>T) (HBA1:c.300+55G>T) and hemoglobin (Hb) Maranon (HBA2:c.94A>G) were first identified in the Chinese population. We also identified rare Hb variants of HbC, HbG-Honolulu, Hb Miyashiro, and HbG-Coushatta in this study. Conclusions.--TGS technology can effectively and accurately detect deletional and nondeletional thalassemia variants simultaneously in one experiment. Our study also demonstrated the application value of TGS-based comprehensive analysis of thalassemia alleles in the detection of rare thalassemia gene variants. doi: 10.5858/arpa.2021-0510-OA, Thalassemia is a common inherited blood disorder resulting from deficient synthesis of globin chains. (1) According to the deficiency of globin genes, thalassemia can be classified into [alpha], [beta], [delta], [...]

Background: Congenital hemidysplasia with ichthyosiform nevus and limb defects (CHILD) syndrome is a rare X‐linked dominant, lethal male disorder caused by mutations to the NSDHL (NAD(P)H steroid dehydrogenase‐like protein) gene. It primarily exhibits strictly unilateral congenital hemidysplasia with ichthyosiform erythroderma and ipsilateral limb defects in female individuals. Methods: A Chinese couple suffering from recurrent spontaneous abortion in male fetuses was enrolled in this study. Chromosomal microarray analysis and whole‐exome sequencing were performed for genetic etiological diagnosis. Results: A 33‐year‐old pregnant woman with recurrent spontaneous abortion was experiencing her third pregnancy with a male embryo. In this pregnancy, a miscarriage occurred at a gestational age of 10+6 weeks with no copy number variants. However, a novel mutation c.790‐6C>T in the NSDHL gene was observed in the fetus through whole‐exome sequencing (WES). Parental verification indicated that the NSDHL gene variant was inherited from the mother. Additionally, the variant in the NSDHL gene was absent in her subsequent pregnancy with a female fetus. Conclusion: In this study, we detected c.790‐6C>T, a novel variant in the NSDHL gene that results in recurrent miscarriage in males. Our study may broaden the scope of research on the NSDHL gene in CHILD syndrome and strengthens the application value of WES for the genetic etiological identification of recurrent miscarriage. [ABSTRACT FROM AUTHOR]

Background: Oculofaciocardiodental (OFCD) syndrome is an X-linked dominant syndrome caused by BCOR variants , which manifests only in females and presumed leading to male lethality. Herein, we aim to present a prenatal diagnosis for OFCD syndrome associated with a novel hemizygous variant in BCOR gene. Case presentation: A 29-year-old pregnant woman from Quanzhou Fujian Province, China, with fetal ultrasound anomalies, was enrolled in this study. A normal 46, XY karyotype with no abnormalities was observed in the fetus detected on microarray. Furthermore, a whole-exome sequencing (WES) detection result demonstrated that a novel hemizygous variant of c.251dupT (p.N87Kfs*6) in the BCOR gene was identified in the fetus, which was a frameshift mutation and classified as a likely pathogenic variant, and may lead to OFCD syndrome according to the clinical feature of the fetus. In this case, male lethality had not occurred by the end of the second trimester, then termination of the pregnancy was conducted at a gestational age of 26 weeks. Sanger sequencing of parental samples revealed that the variant was maternally transmitted, which was consistent with the OFCD syndrome phenotypic features observed in her. Conclusions: In the study, we first present the affected male with a novel variant in BCOR that leads to the OFCD syndrome. Additionally, our study broadened the spectrum of BCOR results in the OFCD syndrome and provided the valuable references for prenatal genetic consultation. [ABSTRACT FROM AUTHOR]

Background: There are limited reports available on investigations into the molecular spectrum of thalassemia and hemoglobinopathy in Fujian province, Southeast China. Here, we aim to reveal the spectrum of the thalassemia mutation and hemoglobinopathy in Quanzhou prefecture, Fujian province. Methods: We collected data from a total of 17,407 subjects with the thalassemia trait in Quanzhou prefecture. Gap-PCR, DNA reverse dot blot hybridization, and DNA sequencing were utilized for common and rare thalassemia gene testing. Results: In our study, we identified 7,085 subjects who were carrying thalassemia mutations, representing a detection rate of 40.70% (7,085/17,407). Among them, 13 different α-thalassemia gene mutations were detected, with the most common mutation being – SEA (69.01%), followed by –α3.7 (21.34%) and –α4.2 (3.96%). We also discovered 26 β-thalassemia gene mutations, with the mutations of IVS-II-654 (C > T) (36.28%) and CD41/42(–TCTT) (29.16%) being the most prevalent. Besides, a variety of rare thalassemia variants were identified. Among them, the – FIL , β Malay , β IVS–I– 130, and β IVS–II– 672 mutations were identified in Fujian province for the first time. Additionally, we detected 78 cases of hemoglobinopathies, of which Hb Owari was the first reported case in Fujian province and Hb Miyashiro was the first case identified in the Chinese population. Conclusion: Our study indicates that there is a diverse range of thalassemia mutations, and it also reveals the mutation spectrum of rare thalassemia and hemoglobinopathies in Quanzhou, Fujian province. It provides valuable data for the prevention and control of thalassemia in Southeast China. [ABSTRACT FROM AUTHOR]

Syndactyly is one of the most frequent hereditary limb malformations with clinical and genetical complexity. Autosomal dominant syndactyly type IV (SD4) is a rare form of syndactyly, caused by heterozygous mutations in a sonic hedgehog (SHH) regulatory element (ZRS) which resides in intron 5 of the LMBR1 gene on chromosome 7q36.3. SD4 is characterized by complete cutaneous syndactyly of the fingers, accompanied by cup-shaped hands due to flexion of the fingers and polydactyly. Here, for the first time, we reported a large Chinese family from Fujian province, manifesting cup-shaped hands consistent with SD4 and intrafamilial heterogeneity in clinical phenotype of tibial and fibulal shortening, triphalangeal thumb-polysyndactyly syndrome (TPTPS). We identified a novel duplication of ∼222 kb covering exons 2–17 of the LMBR1 gene in this family by sub-exome target sequencing. This case expands our new clinical understanding of SD4 phenotype and again confirms the feasibility to detect copy number variation by sub-exome target sequencing. [ABSTRACT FROM AUTHOR]

Background: α-thalassaemia is an inherited blood disorder caused by mutations in the α-globin gene cluster. Recognizing the pathogenic α-globin gene mutations associated with α-Thalassemia is of significant importance to thalassaemia's diagnosis and management. Methods: A family with α-thalassaemia from Fujian, China was recruited for this study. The phenotype was confirmed through haematological analysis. Commercially available Gap-PCR genotypic methods were employed to identify the known deletions causing α-thalassemia. MLPA analysis was used to study the novel mutations; this was then confirmed through DNA sequencing and bioinformatics analysis. Results: The proband of the family belonged to Southeast Asian type (--SEA) thalassaemia. None of the known mutations associated with α-thalassaemia were detected in this family's genetics, whereas a novel 6.9 kb deletion (16p13.3 g.29,785-36,746) covering the α2 gene on the globin gene cluster was identified with MLPA and confirmed through Sanger Sequencing. This data led us to propose a novel pathogenic deletion associated with α-thalassemia: -α6.9 /--SEA. Conclusions: A novel α-thalassaemia deletion was identified in members of a Chinese family and subsequently analyzed. This finding has helped broaden the spectrum of pathogenic mutations leading to the development of α-thalassaemia, paving the way for improved disease diagnosis and management. [ABSTRACT FROM AUTHOR]

Background: Osteogenesis imperfecta (OI) is a rare heterogeneous disorder typically featured by fragile bones and susceptibility to fracture. The aim of the present study was to explore the genetic etiology of familial recurrent OI and the genotype-phenotype correlation., Methods: Karyotyping, chromosomal microarray analysis, and whole-exome sequencing (WES) were performed to determine the genetic etiology of OI in the enrolled family. Western blotting analysis was carried out using the fetal skin tissue for type I collagen production analysis., Results: At the first pregnancy, a c.1777G>A mutation in the COL1A1 gene was detected in the fetus who exhibited skeletal dysplasia. In this second pregnancy, severe fetal skeletal dysplasia was also presented without significant chromosomal abnormality detected by karyotype and chromosomal microarray analysis in the fetus. Further WES results demonstrated a de novo missense mutation of c.1777G>A (p.G593S) in the fetus, which was classified as a pathogenic variant according to the ACMG guidelines. The recurrent mutation in the two fetuses hinted at the possible existence of gonadal mosaicism in the parents, while no mutation in the COL1A1 gene was identified in the DNA from the father's sperm. In addition, Western blot results demonstrated no reduced type I procollagen production in the affected fetus compared with the age-matched controls., Conclusions: To the best of our knowledge, this is the first study that identified a rare variant of c.1777G>A in the COL1A1 gene that led to recurrent OI in the Chinese population. Additionally, we believe that this rare variant of c.1777G>A in the COL1A1 gene will lead to OI type II. The results of the present study further verify the application value of WES in identifying fetuses with ultrasound anomalies., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Zhuang, Chen, Chen, Luo, Wang, Jiang, Zeng, Xie and Chen.)

Aims: β-Thalassaemia is an inherited blood disorder caused by mutations in the β-globin gene cluster. Molecular characterisation of β-thalassaemia is essential for its diagnosis and management. More and more rare and novel mutations have been reported., Methods: Two Chinese families with β-thalassaemia from Fujian Province were recruited in this study. The phenotypes of the probands were confirmed through haematological analysis. Routine molecular analysis of thalassaemia was employed to identify the common mutations of thalassaemia. The rare and novel mutations were detected by direct DNA sequencing., Results: In family 1, the proband, a Chinese woman aged 31 years, showed elevated level of haemoglobin A2 (HbA2). No common mutations associated with β-thalassaemia were detected, whereas a rare mutation Term CD+32(HBB: c.32A>C) was identified through DNA sequencing. Subsequent investigation of the β-thalassaemia mutation in her family showed that her mother, her brother as well as her nephew also carried this mutation. In addition, both the proband's husband and her son carrying the rare -- THAI mutation exhibited decreased levels of MCH, MCH and HbA2. In family 2, the proband, a child aged 1 year, showed elevated level of HbA2, but had no common mutations of β-thalassaemia. The proband was identified carrying the mutation Term CD+32(HBB: c.32A>C), which was inherited from his mother., Conclusions: In this study, we first report a rare β-thalassaemia mutation in Fujian Province, Southeast China. Moreover, our study also identified this rare mutation in humans. This finding has helped broaden the spectrum of β-thalassaemia mutations in our region and suggested that this rare mutation may be more prevalent in the Chinese population., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. No commercial re-use. See rights and permissions. Published by BMJ.)

Aims: Thalassemia is one of the most prevalent inherited disorders in south China. However, there still has no comprehensive research on molecular characterisation of α-thalassemia and β-thalassemia in the Quanzhou region of Fujian province, a city with high incidence of thalassemia in Southeast China., Methods: A total of 11 668 cases were collected in Quanzhou region from January 2013 to June 2019. The deletions of α-thalassemia were detected by Gap-PCR, α-thalassemia and β-thalassemia mutations were detected by DNA reverse dot blot hybridisation. Rare thalassemia gene testing and DNA sequencing were performed to detect rare and novel thalassemia mutation for suspected rare thalassemia carriers., Results: Among 11 668 subjects, 4796 (41.10%) subjects were diagnosed with thalassemia. 3298 (28.27%) subjects were α-thalassemia carriers, 26 types of α-thalassemia mutations were identified, with the common α-thalassemia genotypes being -- SEA /αα (71.47%), -α 3.7 /αα (17.13%) and -α 4.2 /αα (3.49%). 1407 (12.06%) subjects were β-thalassemia carriers, 18 types of β-thalassemia mutations were identified. The common five genotypes of β-thalassemia were β IVS-II-654 /β N (36.53%), β CD41-42 /β N (30.28%), β CD17 /β N (17.13%), β CD26 /β N (5.12%) and β -28 /β N (4.62%). Additionally, 91 (0.78%) subjects with composite α-thalassemia and β-thalassemia were identified. Furthermore, 9 α-thalassemia and β-thalassemia gene mutations (CAP +40-43 (-AAAC), IVS-I-1 (G>T), IVS-I-5 (G>C), SEA-HPFH, CD53 (-T), CD37 (A>G), -90 (C>T), CD3 (T>C), -α 6.9 ) were identified for the first time in the region. Among them, CD53 (-T), CD37 (A>G) and -90 (C>T) mutations were identified for the first time in Fujian province. Moreover, CD3 (T>C), -α 6.9 mutations were first identified in Chinese individual., Conclusions: Quanzhou region of South China has high incidence of thalassemia mutations. In this study, several cases of rare thalassemia mutations have been identified, providing reference for clinical consultation. The completion of this study is of great significance to strengthen the prevention and control of thalassaemia in the Quanzhou region., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: α-thalassaemia is an inherited blood disorder caused by mutations in the α-globin gene cluster. Recognizing the pathogenic α-globin gene mutations associated with α-Thalassemia is of significant importance to thalassaemia's diagnosis and management., Methods: A family with α-thalassaemia from Fujian, China was recruited for this study. The phenotype was confirmed through haematological analysis. Commercially available Gap-PCR genotypic methods were employed to identify the known deletions causing α-thalassemia. MLPA analysis was used to study the novel mutations; this was then confirmed through DNA sequencing and bioinformatics analysis., Results: The proband of the family belonged to Southeast Asian type (-- SEA ) thalassaemia. None of the known mutations associated with α-thalassaemia were detected in this family's genetics, whereas a novel 6.9 kb deletion (16p13.3 g.29,785-36,746) covering the α2 gene on the globin gene cluster was identified with MLPA and confirmed through Sanger Sequencing. This data led us to propose a novel pathogenic deletion associated with α-thalassemia: -α 6.9 /-- SEA ., Conclusions: A novel α-thalassaemia deletion was identified in members of a Chinese family and subsequently analyzed. This finding has helped broaden the spectrum of pathogenic mutations leading to the development of α-thalassaemia, paving the way for improved disease diagnosis and management.