Expression and localization of HSD17B13 along mouse urinary tract.

17ß-Hydroxysteroid dehydrogenase-13 (HSD17B13), a newly identified lipid droplet-associated protein, plays an important role in the development of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH). Emerging evidence demonstrates that NASH is an independent risk factor for chronic kidney disease, which is frequently accompanied by renal lipid accumulation. In addition, the HSD17B13 rs72613567 variant is associated with lower levels of albuminuria in patients with biopsy-proven NAFLD. At present, the role of HSD17B13 in lipid accumulation in the kidney is unclear. This study utilized bioinformatic and immunostaining approaches to examine the expression and localization of HSD17B13 along the mouse urinary tract. We found that HSD17B13 is constitutively expressed in the kidney, ureter, and urinary bladder. Our findings reveal for the first time, to our knowledge, the precise localization of HSD17B13 in the mouse urinary system, providing a basis for further studying the pathogenesis of HSD17B13 in various renal and urological diseases.NEW & NOTEWORTHY HSD17B13, a lipid droplet-associated protein, is crucial in nonalcoholic fatty liver disease (NAFLD) development. NAFLD also independently raises chronic kidney disease (CKD) risk, often with renal lipid buildup. However, HSD17B13's role in CKD-related lipid accumulation is unclear. This study makes the first effort to examine HSD17B13 expression and localization along the urinary system, providing a basis for exploring its physiological and pathophysiological roles in the kidney and urinary tract.

Pregnane X receptor activation alleviates renal fibrosis in mice via interacting with p53 and inhibiting the Wnt7a/ß-catenin signaling.

Renal fibrosis is a common pathological feature of chronic kidney disease (CKD) with various etiologies, which seriously affects the structure and function of the kidney. Pregnane X receptor (PXR) is a member of the nuclear receptor superfamily and plays a critical role in regulating the genes related to xenobiotic and endobiotic metabolism in mammals. Previous studies show that PXR is expressed in the kidney and has protective effect against acute kidney injury (AKI). In this study, we investigated the role of PXR in CKD. Adenine diet-induced CKD (AD) model was established in wild-type and PXR humanized (hPXR) mice, respectively, which were treated with pregnenolone-16α-carbonitrile (PCN, 50 mg/kg, twice a week for 4 weeks) or rifampicin (RIF, 10 mg·kg-1·d-1, for 4 weeks). We showed that both PCN and RIF, which activated mouse and human PXR, respectively, improved renal function and attenuated renal fibrosis in the two types of AD mice. In addition, PCN treatment also alleviated renal fibrosis in unilateral ureter obstruction (UUO) mice. On the contrary, PXR gene deficiency exacerbated renal dysfunction and fibrosis in both adenine- and UUO-induced CKD mice. We found that PCN treatment suppressed the expression of the profibrotic Wnt7a and ß-catenin in AD mice and in cultured mouse renal tubular epithelial cells treated with TGFß1 in vitro. We demonstrated that PXR was colocalized and interacted with p53 in the nuclei of tubular epithelial cells. Overexpression of p53 increased the expression of Wnt7a, ß-catenin and its downstream gene fibronectin. We further revealed that p53 bound to the promoter of Wnt7a gene to increase its transcription and ß-catenin activation, leading to increased expression of the downstream profibrotic genes, which was inhibited by PXR. Taken together, PXR activation alleviates renal fibrosis in mice via interacting with p53 and inhibiting the Wnt7a/ß-catenin signaling pathway.

Germline intergenic duplications at Xq26.1 underlie Bazex-Dupré-Christol basal cell carcinoma susceptibility syndrome.

BACKGROUND: Bazex-Dupré-Christol syndrome (BDCS; MIM301845) is a rare X-linked dominant genodermatosis characterized by follicular atrophoderma, congenital hypotrichosis and multiple basal cell carcinomas (BCCs). Previous studies have linked BDCS to an 11·4-Mb interval on chromosome Xq25-q27.1. However, the genetic mechanism of BDCS remains an open question. OBJECTIVES: To investigate the genetic aetiology and molecular mechanisms underlying BDCS. METHODS: We ascertained multiple individuals from eight unrelated families affected with BDCS (F1-F8). Whole-exome (F1 and F2) and genome sequencing (F3) were performed to identify putative disease-causing variants within the linkage region. Array comparative genomic hybridization and quantitative polymerase chain reaction (PCR) were used to explore copy number variations, followed by long-range gap PCR and Sanger sequencing to amplify the duplication junctions and to define the head-tail junctions. Hi-C was performed on dermal fibroblasts from two affected individuals with BDCS and one control. Public datasets and tools were used to identify regulatory elements and transcription factor binding sites within the minimal duplicated region. Immunofluorescence was performed in hair follicles, BCCs and trichoepitheliomas from patients with BDCS and sporadic BCCs. The ACTRT1 variant c.547dup (p.Met183Asnfs*17), previously proposed to cause BDCS, was evaluated with t allele frequency calculator. RESULTS: In eight families with BDCS, we identified overlapping 18-135-kb duplications (six inherited and two de novo) at Xq26.1, flanked by ARHGAP36 and IGSF1. Hi-C showed that the duplications did not affect the topologically associated domain, but may alter the interactions between flanking genes and putative enhancers located in the minimal duplicated region. We detected ARHGAP36 expression near the control hair follicular stem cell compartment, and found increased ARHGAP36 levels in hair follicles in telogen, in BCCs and in trichoepitheliomas from patients with BDCS. ARHGAP36 was also detected in sporadic BCCs from individuals without BDCS. Our modelling showed the predicted maximum tolerated minor allele frequency of ACTRT1 variants in control populations to be orders of magnitude higher than expected for a high-penetrant ultra-rare disorder, suggesting loss of function of ACTRT1 variants to be an unlikely cause for BDCS. CONCLUSIONS: Noncoding Xq26.1 duplications cause BDCS. The BDCS duplications most likely lead to dysregulation of ARHGAP36. ARHGAP36 is a potential therapeutic target for both inherited and sporadic BCCs. What is already known about this topic? Bazex-Dupré-Christol syndrome (BDCS) is a rare X-linked basal cell carcinoma susceptibility syndrome linked to an 11·4-Mb interval on chromosome Xq25-q27.1. Loss-of-function variants in ACTRT1 and its regulatory elements were suggested to cause BDCS. What does this study add? BDCS is caused by small tandem noncoding intergenic duplications at chromosome Xq26.1. The Xq26.1 BDCS duplications likely dysregulate ARHGAP36, the flanking centromeric gene. ACTRT1 loss-of-function variants are unlikely to cause BDCS. What is the translational message? This study provides the basis for accurate genetic testing for BDCS, which will aid precise diagnosis and appropriate surveillance and clinical management. ARHGAP36 may be a novel therapeutic target for all forms of sporadic basal cell carcinomas.

Lack of MECP2 gene transcription on the duplicated alleles of two related asymptomatic females with Xq28 duplications and opposite X-chromosome inactivation skewing.

Xq28 duplication syndrome (MIM# 300815) is a severe neurodevelopmental disorder in males due to MeCP2 overexpression. Most females with MECP2 duplication are asymptomatic carriers, but there are phenotypic heterogeneities. Skewed X-chromosome inactivation (XCI) can protect females from exhibiting clinical phenotypes. Herein we reported two asymptomatic females (mother and grandmother) with interstitial Xq28 duplication. AR and RP2 assays showed that both had extremely skewed XCI, the Xq28 duplicated chromosome was inactivated in the mother, but was surprisingly activated in the grandmother. Interestingly, by combining RNA sequencing and whole-exome sequencing, we confirmed that XIST only expressed in the Xq28 duplication chromosomes of the two females, indicating that the Xq28 duplication chromosomes were inactive. Meanwhile, MECP2 and most XCI genes in the duplicated X-chromosomes were not transcriptionally expressed or upregulated, precluding major clinical phenotypes in the two females, especially the grandmother. We showed that XCI status detected using RNA sequencing was more relevant for establishing the clinical phenotype of MECP2 duplication in females. It suggested that there were other factors maintaining the XCI status in addition to DNA methylation, a possible additional inhibition mechanism occurred at the transcriptional level in the unmethylated X-chromosome, counter balancing the MECP2 duplication's detrimental phenotype effects.

[Genetic Study and Prenatal Diagnosis of a Family with Thrombocytopenia-Absent Radius (TAR) Syndrome].

OBJECTIVE: To analyze the potential genetic cause of thrombocytopenia-absent radius (TAR) syndrome in a family and provide prenatal diagnosis for them. METHODS: Genetic mutation analysis of the sporadic family with TAR syndrome was performed with chromosome microarray analysis (CMA), quantitative polymerase chain reaction (qPCR) and Sanger sequencing. DNA samples were collected from 4 members of the family, including the proband, her parents and her sister. CMA, qPCR and Sanger sequencing were performed to determine the pathogenic mutation and prenatal diagnosis of the fetus was made accordingly. RESULTS: The proband had a 378 kb genomic heterozygous deletion in 1q21.1, which contained RBM8 A and other genes. c.-21G>A mutation was also found in the RBM8 A of the proband. The above-mentioned microdeletion and mutation were inherited from the mother and father, respectively. Prenatal CMA suggested that the fetus carried a 378 kb microdeletion in 1q21.1, and DNA testing did not find c.-21G>A mutation. CONCLUSION: The heterozygous deletion in 1q21.1 and RBM8 A: c.-21G>A is considered to be the genetic etiology of TAR syndrome in the family. The study provides information for subsequent family genetic counseling and prenatal diagnosis.

Preimplantation genetic diagnosis and screening (PGD/S) using a semiconductor sequencing platform.

BACKGROUND: Recent advances in semiconductor sequencing platform (SSP) have provided new methods for preimplantation genetic diagnosis/screening (PGD/S). The present study aimed to evaluate the applicability and efficiency of SSP in PGD/S. METHODS: The artificial positive single-cell-like DNAs and normal single-cell samples were chosen to test our semiconductor sequencing platform for preimplantation genetic diagnosis/screening (SSP-PGD/S) method with two widely used whole-genome amplification (WGA) kits. A total of 557 single blastomeres were collected from in vitro fertilization (IVF) couples, and their WGA products were processed and analyzed by our SSP-PGD/S method in comparison with array comparative genomic hybridization (array-CGH). RESULTS: Our SSP-PGD/S method indicated high compatibilities with two commercial WGA kits. For 557 single blastomeres, our method with four million reads in average could detect 24-chromosome aneuploidies as well as microdeletion/microduplication of the size over 4 Mb, providing 100% consistent conclusion with array-CGH method in the classification of whether it was transplantable. CONCLUSIONS: Our studies suggested that SSP-PGD/S represents a valuable alternative to array-CGH and brought PGD/S into a new era of more rapid, accurate, and economic.

[Genetic study of a family of neuronal ceroid lipofuscinosis caused by a heterozygous mutation of CLN6 gene].

OBJECTIVE: To analyze the genetic cause of a family with autosomal recessive neuronal ceroid lipofuscinoses (NCL). METHODS: The proband was screened for mutations within the coding region of the candidate genes through high-throughput targeted sequencing. Potential causative mutations were verified by PCR and Sanger sequencing in the proband and his parents. RT-PCR and TA clone sequencing were performed to investigate whether the mRNAs were abnormally spliced. RESULTS: The sequencing results revealed compound heterozygous mutations of CLN6:c.486+2T>C and c.486+4A>T, which were respectively inherited from his parents. RT-PCR and TA cloning sequencing suggested that the mRNAs were abnormally spliced in two forms due to both mutations. CONCLUSIONS: The compound heterozygous mutations of CLN6:c.486+2T>C and c.486+4A>T are possibly the genetic causes of the NCL family. Detection of the novel mutation has extended mutation spectrum of CLN6.

[Genetic analysis and prenatal diagnosis of a sporadic family with neurofibromatosis type 1].

OBJECTIVE: To identify pathogenic mutation for a family with neurofibromatosis type 1(NF1) and provide prenatal diagnosis for them. METHODS: Mutation analysis of the sporadic family with NF1 was performed with target captured next generation sequencing and Sanger sequencing. RNA samples were extracted from the lymphocytes of NF1 patient and her parents. RT-PCR and Sanger sequencing were performed to analyze the relative mRNA expression in the samples. Prenatal diagnosis of the pathogenic mutation was offered to the fetus. RESULTS: A novel splicing mutation c.1260+4A>T in the NF1 gene was found in the proband of the family, but was not found in her parents.cDNA sequencing showed that 13 bases inserted into the 3' end of exon 11 in the NF1 gene lead to a frameshift mutation. Prenatal diagnosis suggested that the fetus did not carried the mutant. CONCLUSIONS: The NF1: c.1260+4A>T mutation found in the NF1 patient is considered to be pathogenic, which provides information for family genetic counseling and prenatal diagnosis.

[Identification of a novel mutation of DSPP gene in a Chinese family affected with dentinogenesis imperfecta shields type II].

OBJECTIVE: To identify the causative mutation in a Chinese family affected with dentinogenesis imperfecta shields type II (DGI-II). METHODS: With informed consent obtained from all participants, peripheral blood or chorionic villi samples were collected from the family members. Genomic DNA was extracted using a standard SDS-proteinase K-phenol/chloroform method. The whole coding region and exon/intron boundaries of the DSPP gene were amplified with polymerase chain reaction (PCR) and subjected to Sanger sequencing. To confirm the pathogenicity of the identified mutation, an Alu I recognition sequence was introduced into the mutant allele using mismatch primers by semi-nested PCR. Restriction fragment length polymorphism (RFLP) analysis was then carried out for all family members and 60 unrelated healthy controls. Meanwhile, mini-DSPP constructs were conducted to confirm the effect of the mutation in vitro. RESULTS: A splicing site mutation, c.52-1G>A, which was located upstream of exon 3, was found in all three patients and the fetus of the proband. Restriction analysis confirmed that all unaffected individuals and the 60 healthy controls did not carry the same mutation. The expression of minigene showed that the exon 3 of the DSPP gene was skipped during the transcription. CONCLUSION: A novel pathogenic splicing-mutation c.52-1G>A has been detected in a Chinese family affected with DGI-II, which enabled prenatal diagnosis for the fetus of the proband.

[Identification of a pathogenic microduplication in a Chinese split-hand/split-foot malformation family].

OBJECTIVE To identify the potential pathogenic mutation in a Chinese family with split hand/foot malformation (SHFM). METHODS Affymetrix SNP 6.0 array was used to perform a genome-wide copy number variations scan, and quantitative real-time PCR (qPCR) was applied to validate the identified genomic duplication. RESULTS A ~560 kb microduplication on the chromosome 10q24 was identified. The qPCR assay confirmed the presence of this microduplication in all the available affected family members. CONCLUSION The ~560 kb microduplication is probably the pathogenic mutation underlying the SHFM phenotype in the studied family.

Identification of four TTN variants in three families with fetal akinesia deformation sequence.

BACKGROUND: TTN is a complex gene with large genomic size and highly repetitive structure. Pathogenic variants in TTN have been reported to cause a range of skeletal muscle and cardiac disorders. Homozygous or compound heterozygous mutations tend to cause a wide spectrum of phenotypes with congenital or childhood onset. The onset and severity of the features were considered to be correlated with the types and location of the TTN variants. METHODS: Whole-exome sequencing was performed on three unrelated families presenting with fetal akinesia deformation sequence (FADS), mainly characterized by reduced fetal movements and limb contractures. Sanger sequencing was performed to confirm the variants. RT-PCR analysis was performed. RESULTS: TTN c.38,876-2 A > C, a meta transcript-only variant, with a second pathogenic or likely pathogenic variant in trans, was observed in five affected fetuses from the three families. Sanger sequencing showed that all the fetal variants were inherited from the parents. RT-PCR analysis showed two kinds of abnormal splicing, including intron 199 extension and skipping of 8 bases. CONCLUSIONS: Here we report on three unrelated families presenting with FADS caused by four TTN variants. In addition, our study demonstrates that pathogenic meta transcript-only TTN variant can lead to defects which is recognizable prenatally in a recessive manner.

A large-scale production of mesenchymal stem cells and their exosomes for an efficient treatment against lung inflammation.

Mesenchymal stem cells (MSCs) and their produced exosomes have demonstrated inherent capabilities of inflammation-guided targeting and inflammatory modulation, inspiring their potential applications as biologic agents for inflammatory treatments. However, the clinical applications of stem cell therapies are currently restricted by several challenges, and one of them is the mass production of stem cells to satisfy the therapeutic demands in the clinical bench. Herein, a production of human amnion-derived MSCs (hMSCs) at a scale of over 1 × 109 cells per batch was reported using a three-dimensional (3D) culture technology based on microcarriers coupled with a spinner bioreactor system. The present study revealed that this large-scale production technology improved the inflammation-guided migration and the inflammatory suppression of hMSCs, without altering their major properties as stem cells. Moreover, these large-scale produced hMSCs showed an efficient treatment against the lipopolysaccharide (LPS)-induced lung inflammation in mice models. Notably, exosomes collected from these large-scale produced hMSCs were observed to inherit the efficient inflammatory suppression capability of hMSCs. The present study showed that 3D culture technology using microcarriers coupled with a spinner bioreactor system can be a promising strategy for the large-scale expansion of hMSCs with improved anti-inflammation capability, as well as their secreted exosomes.

An efficient molecular genetic testing strategy for incontinentia pigmenti based on single-tube long fragment read sequencing.

Incontinentia pigmenti (IP) is a rare X-linked dominant neuroectodermal dysplasia that primarily affects females. The only known causative gene is IKBKG, and the most common genetic cause is the recurrent IKBKG△4-10 deletion resulting from recombination between two MER67B repeats. Detection of variants in IKBKG is challenging due to the presence of a highly homologous non-pathogenic pseudogene IKBKGP1. In this study, we successfully identified four pathogenic variants in four IP patients using a strategy based on single-tube long fragment read (stLFR) sequencing with a specialized analysis pipeline. Three frameshift variants (c.519-3_519dupCAGG, c.1167dupC, and c.700dupT) were identified and subsequently validated by Sanger sequencing. Notably, c.519-3_519dupCAGG was found in both IKBKG and IKBKGP1, whereas the other two variants were only detected in the functional gene. The IKBKG△4-10 deletion was identified and confirmed in one patient. These results demonstrate that the proposed strategy can identify potential pathogenic variants and distinguish whether they are derived from IKBKG or its pseudogene. Thus, this strategy can be an efficient genetic testing method for IKBKG. By providing a comprehensive understanding of the whole genome, it may also enable the exploration of other genes potentially associated with IP. Furthermore, the strategy may also provide insights into other diseases with detection challenges due to pseudogenes.

Impact of Time-Restricted Feeding on Adaptation to a 6-Hour Delay Phase Shift or a 12-Hour Phase Shift in Mice.

Nowadays, more and more people are suffering from circadian disruption. However, there is no well-accepted treatment. Recently, time-restricted feeding (TRF) was proposed as a potential non-drug intervention to alleviate jet lag in mice, especially in mice treated with a 6-h advanced phase shift. Here, we challenged C57BL/6 mice with a 6-h delay phase shift or a 12-h shift (day-night reversal) combined with 6- or 12-h TRF within the dark phase and found the beneficial effects of given TRF strategies in certain phase-shifting situations. Although behavioral fitness did not correlate well with health status, none of the TRF strategies we used deteriorated lipopolysaccharide-induced sepsis. These findings improve our understanding of the benefits of TRF for adaptation to circadian disruption.

Identification of of a PAX2 mutation from maternal mosaicism causes recurrent renal disorder in siblings.

BACKGROUND: PAX2-related disorder is an autosomal dominant disorder characterized by renal and eye abnormalities. Some patients may present with isolated renal abnormalities without obvious ocular abnormalities. It is associated with mutations in paired box gene 2 (PAX2), which is one of the families of paired box transcription factor genes. Studies on mosaicism have been limited in PAX2-related disorder, as only three families with mosaic PAX2 mutations have been reported in the literature. METHODS: The proband with multicystic dysplastic kidneys from a Chinese family was recruited in our study. Detailed clinical symptoms were enquired. Trio-based whole exome sequencing (WES), SNP array, sanger sequencing and droplet digital PCR (ddPCR) were used to characterize etiology in the proband. Prenatal diagnosis was performed through amniocentesis and prenatal ultrasound when the proband's mother was further pregnant at 20 weeks. RESULTS: A heterozygous missense mutation in PAX2 (c.194 T > C) was identified in the proband. His asymptomatic mother has the same mutation with somatic mosaicism ratio of 22%. The mutation was also detected in the fetus. Prenatal ultrasound showed that bilateral hyperechogenic kidneys with decrease of renal size. CONCLUSIONS: This is the first report on PAX2 mosaicism in a Chinese family. Identifying PAX2 mosaicism provides more evidence for estimating recurrence risk. Our findings have important implications on genetic counseling for patients with PAX2-related disorder and provide an effective diagnostic technology for mosaicism.

Nuclear receptors in renal health and disease.

As a major social and economic burden for the healthcare system, kidney diseases contribute to the constant increase of worldwide deaths. A deeper understanding of the underlying mechanisms governing the etiology, development and progression of kidney diseases may help to identify potential therapeutic targets. As a superfamily of ligand-dependent transcription factors, nuclear receptors (NRs) are critical for the maintenance of normal renal function and their dysfunction is associated with a variety of kidney diseases. Increasing evidence suggests that ligands for NRs protect patients from renal ischemia/reperfusion (I/R) injury, drug-induced acute kidney injury (AKI), diabetic nephropathy (DN), renal fibrosis and kidney cancers. In the past decade, some breakthroughs have been made for the translation of NR ligands into clinical use. This review summarizes the current understanding of several important NRs in renal physiology and pathophysiology and discusses recent findings and applications of NR ligands in the management of kidney diseases.

Case report: Prenatal diagnosis of fetal intracranial hemorrhage due to compound mutations in the JAM3 gene.

Intracranial hemorrhage is a common complication in preterm infants but occasionally occurs in fetuses. Disruptions of the genes, such as the COL4A1 and COL4A2 genes, are common genetic causes identified in fetal intracranial hemorrhage; however, the disruptions of the JAM3 gene are rarely reported. In the current investigation, fetal intracranial hemorrhage and dilated lateral ventricles were observed in three consecutive siblings in a pedigree. The pregnancies were terminated, and whole-exome sequencing, followed by Sanger sequencing, was performed on the affected fetuses. Pre-implantation genetic testing for monogenic diseases was performed to avoid the recurrence. The compound heterozygous variants of c.712 + 2T > A and c.813C > G p.Tyr271* in the JAM3 gene (NM_032801.4) were identified in the proband and its affected brother, which were predicted to be pathogenic. The variant of c.813C > G p.Tyr271* but not c.712 + 2T > A was identified in the fourth fetus, implying a good prognosis. Our findings expanded the spectrum of the pathogenic mutations in the JAM3 gene and revealed an important application of fetal whole-exome sequencing in idiopathic fetal intracranial hemorrhage.

Keratin 5-Cre-driven deletion of Ncstn in an acne inversa-like mouse model leads to a markedly increased IL-36a and Sprr2 expression.

Familial acne inversa (AI) is an autoinflammatory disorder that affects hair follicles and is caused by loss-of-function mutations in γ-secretase component genes. We and other researchers showed that nicastrin (NCSTN) is the most frequently mutated gene in familial AI. In this study, we generated a keratin 5-Cre-driven epidermis-specific Ncstn conditional knockout mutant in mice. We determined that this mutant recapitulated the major phenotypes of AI, including hyperkeratosis of hair follicles and inflammation. In Ncstnflox/flox;K5-Cre mice, the IL-36a expression level markedly increased starting from postnatal day 0 (P0), and this increase occurred much earlier than those of TNF-α, IL-23A, IL-1ß, and TLR4. RNA-Seq analysis indicated that Sprr2d, a member of the small proline-rich protein 2 family, in the skin tissues of the Ncstnflox/flox;K5-Cre mice was also upregulated on P0. Quantitative reverse-transcription polymerase chain reaction showed that other Sprr2 genes had a similar expression pattern. Our findings suggested that IL-36a might be a key inflammatory cytokine in the pathophysiology of AI and involved in the malfunction of the skin barrier in the pathogenesis of AI.

Generation of the human induced pluripotent stem cell line (ZJUi005-A) from a patient with Pelizaeus-Merzbacher disease (PMD) carrying a novel hemizygous mutation in PLP1 gene.

Pelizaeus-Merzbacher disease (PMD) is a rare X-linked leukodystrophy caused by mutations in the proteolipid protein 1 gene (PLP1) which is specifically expressed on the myelin sheath of oligodendrocytes. We established an induced pluripotent stem cell (iPSC) line (ZJUi005-A) from peripheral blood mononuclear cells of an 18-year-old male PMD patient with a novel hemizygous c.437T>C mutation in PLP1 gene using episomal reprogramming plasmids. The ZJUi005-A iPSC line carried the PLP1 mutation, expressed pluripotency markers, exhibited normal karyotype and showed differentiation potential in vitro.

Comprehensive genetic diagnosis of patients with Duchenne/Becker muscular dystrophy (DMD/BMD) and pathogenicity analysis of splice site variants in the DMD gene.

Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) are caused by mutations in the DMD gene. The aim of this study is to identify pathogenic DMD variants in probands and reduce the risk of recurrence of the disease in affected families. Variations in 100 unrelated DMD/BMD patients were detected by multiplex ligation-dependent probe amplification (MLPA) and next-generation sequencing (NGS). Pathogenic variants in DMD were successfully identified in all cases, and 11 of them were novel. The most common mutations were intragenic deletions (69%), with two hotspots located in the 5' end (exons 2-19) and the central of the DMD gene (exons 45-55), while point mutations were observed in 22% patients. Further, c.1149+1G>A and c.1150-2A>G were confirmed by hybrid minigene splicing assay (HMSA). This two splice site mutations would lead to two aberrant DMD isoforms which give rise to severely truncated protein. Therefore, the clinical use of MLPA, NGS, and HMSA is an effective strategy to identify variants. Importantly, eight embryos were terminated pregnancies according to prenatal diagnosis and a healthy boy was successfully delivered by preimplantation genetic diagnosis (PGD). Early and accurate genetic diagnosis is essential for prenatal diagnosis/PGD to reduce the risk of recurrence of DMD in affected families.