Genotype-phenotype correlation study of structural abnormalities in a fetal brain caused by a novel KDM4B variant.

BACKGROUND: Fetal ventriculomegaly (VM), a common brain structure malformation detected during prenatal ultrasound diagnosis, is associated with an increased risk of neurodevelopmental disorders (NDDs) after birth. KDM4B encodes a lysine-specific demethylase that interacts with histone H3K23me3. Variations in KDM4B are reportedly associated with human NDDs; however, only 11 such patients have been reported. Herein, we report a fetus with VM and agenesis of the corpus callosum (ACC), which suggests that KDM4B plays an important role in fetal brain development. METHODS: Fetal skin tissue and parental peripheral venous blood samples were collected. Whole-exome and Sanger sequencing were performed to analyze fetal germline variants. Human 293T cells transfected with wild-type or mutant KDM4B were used for western blotting (WB) to analyze protein expression levels. RESULTS: An insertion variant of KDM4B, NM_015015.3: c.2889_2890insGAGAGCATCACGGTGAGCTGTGGGGTGGGGCAGGGGGCGGGGGGAGGCTGGGAGCACAGTGACAACCTGTACCCC, was identified in the fetal tissue; however, the parents carried the wild-type gene. The WB results indicated significantly reduced expression of the mutant protein, likely owing to decreased stability. CONCLUSIONS: The structural abnormalities in the brain of the studied fetus may be attributed to an insertion variant of KDM4B. This study highlights the importance of screening for KDM4B variants and considering potential copy number variations when observing VM or ACC in prenatal ultrasound imaging.

Gain equalization for a few-mode erbium-doped fiber amplifier supporting eight spatial modes.

A trench-assisted ring few-mode erbium-doped fiber amplifier (FM-EDFA) supporting eight spatial modes is designed and proposed in this work. The gain equalization for the FM-EDFA is achieved by selecting the appropriate doping radius and concentration using a particle swarm optimization (PSO) algorithm when only the pump in the fundamental mode (L P 01) is applied. When the signals in the eight spatial modes are simultaneously amplified, the average modal gain is about 20 dB, and the DMG is less than 0.3 dB for a signal at 1550 nm. Considering the gain competition of six wavelength signals, the modal gain and DMG are more than 20 and 1 dB, respectively. In addition, the tolerance analysis for manufacturing with this design is also discussed. For a fluctuation in the refractive index, the average modal gain is about 19.5 dB, and the DMG is 0.77 dB, indicating that the structure has good fabrication tolerance.

Loss of PMFBP1 Disturbs Mouse Spermatogenesis by Downregulating HDAC3 Expression.

PURPOSE: Polyamine modulating factor 1 binding protein (PMFBP1) acts as a scaffold protein for the maintenance of sperm structure. The aim of this study was further to identify the new role and molecular mechanism of PMFBP1 during mouse spermatogenesis. METHODS AND RESULTS: We identified a profile of proteins interacting with PMFBP1 by immunoprecipitation combined with mass spectrometry and demonstrated that class I histone deacetylases, particularly HDAC3 and chaperonin-containing TCP1 subunit 3 (CCT3), were potential interaction partners of PMFBP1 based on network analysis of protein-protein interactions and co-immunoprecipitation. Immunoblotting and immunochemistry assays showed that loss of Pmfbp1 would result in a decline in HDACs and change the proteomic profile of mouse testis, in which differently expressed proteins are associated with spermatogenesis and assembly of flagella, which was proved by proteomic analysis of testis tissue obtained from Pmfbp1-/- mice. After integrating with transcriptome data for Hdac3-/- and Sox30-/- round sperm obtained from a public database, RT-qPCR confirmed ring finger protein 151 (Rnf151) and ring finger protein 133 (Rnf133) were key downstream response factors of the Pmfbp1-Hdac axis affecting mouse spermatogenesis. CONCLUSION: Taken together, this study indicates a previously unidentified molecular mechanism of PMFBP1 in spermatogenesis whereby PMFBP1 interacts with CCT3, affecting the expression of HDAC3, followed by the downregulation of RNF151 and RNF133, resulting in an abnormal phenotype of sperm beyond the headless sperm tails. These findings not only advance our understanding of the function of Pmfbp1 in mouse spermatogenesis but also provide a typical case for multi-omics analysis used in the functional annotation of specific genes.

A novel homozygous missense mutation in AK7 causes multiple morphological anomalies of the flagella and oligoasthenoteratozoospermia.

PURPOSE: To identify the genetic causes of multiple morphological anomalies of the flagella (MMAF) and oligoasthenoteratozoospermia (OAT). METHODS: Whole-exome sequencing (WES) was performed on the proband to identify pathogenic mutation for infertility. Western blotting and immunofluorescence analysis detected the expression level and localization of adenylate kinase 7 (AK7). RESULTS: We identified a novel homozygous missense mutation (NM_152327: c.1846G > A; p.E616K) in AK7 in two brothers with MMAF and OAT from a consanguineous family by WES. Western blotting and immunofluorescence experiments determined that the expression level of AK7 decreased in the sperm from the proband. The proband and his wife underwent two cycles of intracytoplasmic sperm injection (ICSI) treatment but got unfavorable outcomes. CONCLUSION: This study could provide precise genetic diagnosis for the patient and expand the spectrum of AK7 mutations.

Mutations in PMFBP1 Cause Acephalic Spermatozoa Syndrome.

Acephalic spermatozoa syndrome is a severe teratozoospermia that leads to male infertility. Our previous work showed that biallelic SUN5 mutations are responsible for acephalic spermatozoa syndrome in about half of affected individuals, while pathogenic mechanisms in the other individuals remain to be elucidated. Here, we identified a homozygous nonsense mutation in the testis-specific gene PMFBP1 using whole-exome sequencing in a consanguineous family with two infertile brothers with acephalic spermatozoa syndrome. Sanger sequencing of PMFBP1 in ten additional infertile men with acephalic spermatozoa syndrome and without SUN5 mutations revealed two homozygous variants and one compound heterozygous variant. The disruption of Pmfbp1 in male mice led to infertility due to the production of acephalic spermatozoa and the disruption of PMFBP1's cooperation with SUN5 and SPATA6, which plays a role in connecting sperm head to the tail. PMFBP1 mutation-associated male infertility could be successfully overcome by intracytoplasmic sperm injection (ICSI) in both mouse and human. Thus, mutations in PMFBP1 are an important cause of infertility in men with acephalic spermatozoa syndrome.

A homozygous missense mutation in TBPL2 is associated with oocyte maturation arrest and degeneration.

The genetic causes in most of patients with oocyte maturation arrest remain largely unknown. In this study, we identified a homozygous missense mutation (c.895T>C; p.C299R) in TBPL2 (TATA box binding protein like 2) in two infertile sisters with oocyte maturation arrest and degeneration from a consanguineous family by whole-exome sequencing. The TBPL2 mutation is rare and pathogenic, and impaired the transcription initiation function of the protein. Our results showed that TBPL2 mutation might be associated with female infertility due to oocyte maturation arrest and degeneration.

Pathogenesis of acephalic spermatozoa syndrome caused by splicing mutation and de novo deletion in TSGA10.

PURPOSE: To identify the genetic causes for acephalic spermatozoa syndrome. METHODS: Whole-exome sequencing was performed on the proband from a non-consanguineous to identify pathogenic mutations for acephalic spermatozoa syndrome. Quantitative real-time polymerase chain reaction and whole genome sequencing were subjected to detect deletion. The functional effect of the identified splicing mutation was investigated by minigene assay. Western blot and immunofluorescence were performed to detect the expression level and localization of mutant TSGA10 protein. RESULTS: Here, we identified a novel heterozygous splicing mutation in TSGA10 (NM_025244: c.1108-1G > T), while we confirmed that there was a de novo large deletion in the proband. The splicing mutation led to the skipping of the exon15 of TSGA10, which resulted in a truncated protein (p. A370Efs*293). Therefore, we speculated that the splicing mutation might affect transcription and translation without the dosage compensation of a normal allele, which possesses a large deletion including intact TSGA10. Western blot and immunofluorescence demonstrated that the very low expression level of truncated TSGA10 protein led the proband to present the acephalic spermatozoa phenotype. CONCLUSION: Our finding expands the spectrum of pathogenic TSGA10 mutations that are responsible for ASS and male infertility. It is also important to remind us of paying attention to the compound heterozygous deletion in patients from non-consanguineous families, so that we can provide more precise genetic counseling for patients.

A novel homozygous missense mutation of PMFBP1 causes acephalic spermatozoa syndrome.

PURPOSE: To identify the pathogenic mutation in PMFBP1 leading to acephalic spermatozoa syndrome. METHODS: Sanger sequencing was used to screen for mutations in the known pathogenic genes SUN5 and PMFBP1 in a patient with acephalic spermatozoa syndrome. Western blotting and immunofluorescence were used to detect the expression and localization of PMFBP1 in sperm. At the same time, a PMFBP1 mutant was constructed, and the expression level of PMFBP1 protein was further verified by in vitro experiments. RESULTS: We identified a novel homozygous PMFBP1 missense mutation, c.301A>C (p.T101P), in an infertile male from a consanguineous family. Our results showed that the expression of PMFBP1 mutant protein was decreased obviously in sperm of the patient. CONCLUSION: Our results showed that the novel homozygous missense mutation of PMFBP1 may be a cause of acephalic spermatozoa syndrome, which provided a basis for genetic counseling for the patient.

Sperm DNA integrity status is associated with DNA methylation signatures of imprinted genes and non-imprinted genes.

PURPOSE: To evaluate the association between the DNA methylation of specific genes and sperm DNA integrity status in human sperm samples. METHODS: A total of 166 semen samples were evaluated (86 controls and 80 cases with impaired sperm DNA integrity). We detected the methylation status of 257 CpG sites among two imprinted genes (H19 and SNRPN) and four non-imprinted genes related to male infertility (MTHFR, GSTM1, DAZL, and CREM) by using a targeted next-generation sequencing method. RESULTS: Differential methylation was found in 43 CpG sites of the promoters of the six candidate genes. H19, SNRPN, MTHFR, DAZL, GSTM1, and CREM contained 22, 12, 1, 4, 0, and 4 differentially methylated CpG sites (P<0.05), respectively. The imprinting genes were associated with relatively higher rates of differentially methylated CpG sites (28.21% in H19 and 41.38% in SNRPN) than the non-imprinting genes. One CpG site in H19 remained significant after performing strict Bonferroni correction. CONCLUSION: In this study, we found that different site-specific DNA methylation signatures were correlated with sperm DNA integrity status. Further studies are needed to investigate the specific mechanisms leading to the epigenetic modifications.

Novel homozygous CFAP69 mutations in humans and mice cause severe asthenoteratospermia with multiple morphological abnormalities of the sperm flagella.

BACKGROUND: Male infertility is a major issue of human reproduction health. Asthenoteratospermia can impair sperm motility and cause male infertility. Asthenoteratospermia with multiple morphological abnormalities of the flagella (MMAF) presents abnormal spermatozoa with absent, bent, coiled, short and/or irregular-calibre flagella. Previous studies on MMAF reported that genetic defects in cilia-related genes (eg, AKAP4, DNAH1, CFAP43, CFAP44 and CFAP69) are the major cause of MMAF. However, the known MMAF-associated genes are only responsible for approximately 30% to 50% of human cases. We further investigated the cases with MMAF in search of additional genes mutated in this condition. METHODS AND RESULTS: We conducted whole exome sequencing in a male individual with MMAF from a consanguineous Han Chinese family. Sanger sequencing was also conducted in additional individuals with MMAF. Intriguingly, a homozygous frameshift mutation (p.Leu357Hisfs*11) was identified in the gene encoding CFAP69 (cilia and flagella-associated protein 69), which is highly expressed in testis. The subsequent Sanger sequencing of the CFAP69 coding regions among 34 additional individuals with MMAF revealed a case with homozygous nonsense mutation (p.Trp216*) of CFAP69. Both of these CFAP69 loss-of-function mutations were not present in the human population genome data archived in the 1000 Genomes Project and ExAC databases, nor in 875 individuals of two Han Chinese control populations. Furthermore, we generated the knockout model in mouse orthologue Cfap69 using the CRISPR-Cas9 technology. Remarkably, male Cfap69-knockout mice manifested with MMAF phenotypes. CONCLUSION: Our experimental findings elucidate that homozygous loss-of-function mutations in CFAP69 can lead to asthenoteratospermia with MMAF in humans and mice.

A homozygous nonsense mutation of PLCZ1 cause male infertility with oocyte activation deficiency.

PURPOSE: To identify the pathogenic PLCZ1 mutation involved in male infertility and fertilization failure. METHODS: All coding regions of PLCZ1 were sequenced by Sanger sequencing. The expression and localization of PLCZ1 in sperm was determined by Western blotting and immunofluorescence. To promote the fertilization rate, the infertile man with PLCZ1 mutation was treated with intracytoplasmic sperm injection (ICSI) accompanied by assisted oocyte activation (AOA) in the following cycle. RESULT: We identified a novel homozygous PLCZ1 nonsense mutation, c.588C>A (p.Cys196Ter) in an infertile man from a consanguineous family. No PLCZ1 protein was detected by Western blotting and immunofluorescence in ejaculated sperm from the patient. The treatment of ICSI + AOA avoided fertilization failure but did not result in pregnancy in the following cycle. CONCLUSION: Our study confirmed the essential role of PLCZ1 in fertilization and male fertility, which indicated the potential prognostic value of testing for PLCZ1 mutations in primary infertile men with sperm-derived fertilization failure.

Patients with severe asthenoteratospermia carrying SPAG6 or RSPH3 mutations have a positive pregnancy outcome following intracytoplasmic sperm injection.

PURPOSE: To investigate the relation between mutations in ciliopathy-related SPAG6 and RSPH3 and male infertility with severe asthenoteratospermia characterized by multiple flagellar malformations and reveal the intracytoplasmic sperm injection (ICSI) outcomes of those primary ciliary dyskinesia (PCD) patients. METHODS: Whole-exome sequencing was applied to identify the pathogenic genes for the five PCD patients. The ICSI outcomes of those patients were compared with eight DNAH1-mutated patients and 215 oligo-asthenospermia (OAT) patients. RESULTS: We identified, for the first time, the compound heterozygous SPAG6 mutations (c.143_145del: p.48_49del, c.585delA: p.Lys196Serfs*6) in a sporadic PCD patient. Further, a novel homozygous nonsynonymous RSPH3 mutation (c.C799T: p.Arg267Cys) was identified in another PCD patient with consanguineous parents. The pathogenicity of these mutations in the assembly of sperm flagella was confirmed by flagellar ultrastructure analysis, immunofluorescence, and quantitative real-time PCR. All five patients underwent six ICSI cycles. The fertilization rate, blastocyst development rate, and clinical pregnancy rate were 69.3%, 50.0%, and 66.7%, respectively. Four of the five couples, including the subjects carrying mutations in SPAG6 or RSPH3, got healthy children born after ICSI. Additionally, the ICSI outcomes of the five PCD couples were statistically comparable with those of the eight DNAH1-mutated couples and the 215 OAT couples. CONCLUSIONS: Mutations in ciliopathy-related SPAG6 and RSPH3 cause severe asthenoteratospermia characterized by multiple flagellar malformations, resulting in sterility. ICSI is an optimal management with a positive pregnancy outcome.

A novel hemizygous loss-of-function mutation in ADGRG2 causes male infertility with congenital bilateral absence of the vas deferens.

PURPOSE: Cystic fibrosis transmembrane conductance regulator (CFTR) and adhesion G protein-coupled receptor G2 (ADGRG2) have been identified as the main pathogenic genes in congenital bilateral absence of the vas deferens (CBAVD), which is an important cause of obstructive azoospermia. This study aimed to identify the disease-causing gene in two brothers with CBAVD from a Chinese consanguineous family and reveal the intracytoplasmic sperm injection (ICSI) outcomes in these patients. METHODS: Whole-exome sequencing and Sanger sequencing were used to identify the candidate pathogenic genes. Real-time polymerase chain reaction, immunohistochemistry, and immunofluorescence were used to assess the expression of the mutant gene. Moreover, the ICSI results from both patients were retrospectively reviewed. RESULTS: A novel hemizygous loss-of-function mutation (c.G118T: p.Glu40*) in ADGRG2 was identified in both patients with CBAVD. This mutation is absent from the human genome databases and causes an early translational termination in the third exon of ADGRG2. Expression analyses showed that both the ADGRG2 mRNA and the corresponding protein were undetectable in the proximal epididymal tissue of ADGRG2-mutated patients. ADGRG2 expression was restricted to the apical membranes of non-ciliated epithelia in human efferent ducts, which was consistent with a previous report in mice. Both ADGRG2-mutated patients had normal spermatogenesis and had successful clinical outcomes following ICSI. CONCLUSIONS: Our study verifies the pathogenic role of ADGRG2 in X-linked CBAVD and broadens the spectrum of ADGRG2 mutations. In addition, we found positive ICSI outcomes in the two ADGRG2-mutated CBAVD patients.

[Outcomes of assisted reproductive technology for patients with different types of teratozoospermia].

OBJECTIVE: To discuss the outcomes of ICSI in infertile patients with globozoospermia (GS), acephalic spermatozoa syndrome (ASS) or teratozoospermia with miniacrosome and irregular-headed sperm defect (TMRHS). METHODS: This retrospective study included 3 cases of GS, 3 cases of ASS and 2 cases of TMRHS undergoing ICSI. We analyzed the rates of fertilization, cleavage, blastocyst formation, implantation, clinical pregnancy and live birth in the three groups of patients. RESULTS: The patients of the GS and ASS groups all achieved clinical pregnancies and healthy births, but those of the TMRHS group showed a lower fertilization rate than the other two groups and achieved no clinical pregnancy. CONCLUSIONS: ICSI could achieve successful clinical pregnancy in infertile patients with globozoospermia or acephalic spermatozoa syndrome, but no satisfactory clinical outcome in those with miniacrosome and irregular-headed sperm defect, though it has to be further proved by more studies with larger-sized samples.

Biallelic SUN5 Mutations Cause Autosomal-Recessive Acephalic Spermatozoa Syndrome.

Acephalic spermatozoa syndrome is a rare and severe form of teratozoospermia characterized by a predominance of headless spermatozoa in the ejaculate. Family clustering and consanguinity suggest a genetic origin; however, causative mutations have yet to be identified. We performed whole-exome sequencing in two unrelated infertile men and subsequent variant filtering identified one homozygous (c.824C>T [p.Thr275Met]) and one compound heterozygous (c.1006C>T [p.Arg356Cys] and c.485T>A [p.Met162Lys]) SUN5 (also named TSARG4) variants. Sanger sequencing of SUN5 in 15 additional unrelated infertile men revealed four compound heterozygous (c.381delA [p.Val128Serfs∗7] and c.824C>T [p.Thr275Met]; c.381delA [p.Val128Serfs∗7] and c.781G>A [p.Val261Met]; c.216G>A [p.Trp72∗] and c.1043A>T [p.Asn348Ile]; c.425+1G>A/c.1043A>T [p.Asn348Ile]) and two homozygous (c.851C>G [p.Ser284∗]; c.350G>A [p.Gly114Arg]) variants in six individuals. These 10 SUN5 variants were found in 8 of 17 unrelated men, explaining the genetic defect in 47.06% of the affected individuals in our cohort. These variants were absent in 100 fertile population-matched control individuals. SUN5 variants lead to absent, significantly reduced, or truncated SUN5, and certain variants altered SUN5 distribution in the head-tail junction of the sperm. In summary, these results demonstrate that biallelic SUN5 mutations cause male infertility due to autosomal-recessive acephalic spermatozoa syndrome.

NovelCFAP43 andCFAP44 mutations cause male infertility with multiple morphological abnormalities of the sperm flagella (MMAF).

RESEARCH QUESTION: Multiple morphological abnormalities of the sperm flagella (MMAF) comprise a rare congenital disease that can cause primary male infertility. Several pathogenic genes (e.g. AKAP4, DNAH1, CFAP43 and CFAP44) are associated with MMAF but the pathogenic mechanisms have not been elucidated. DESIGN: Whole-exome sequencing (WES) was applied to identify the pathogenic genes in 13 Chinese patients with MMAF; the patients were unrelated but all had consanguineous parents (usually first cousins). Real-time polymerase chain reaction and immunofluorescence staining were employed to assess the pathogenicity of these mutations. RESULTS: Four novel homozygous CFAP43 mutations in four (30.8%) MMAF patients and one novel homozygous CFAP44 mutation in one (7.7%) other case were identified. The four novel homozygous CFAP43 mutations included one frameshift mutation (c.1140_1143del: p.Asn380Lysfs*3), one nonsense mutation (c.739A>T: p.Lys247*) and two missense mutations (c.1474G>C: p.Gln492Arg; c.4600C>G: p.Leu1534Val). The novel mutation in CFAP44 was a homozygous nonsense mutation (c.4963C>T: p.Arg1655*). Co-segregation of the mutations was verified by Sanger sequencing of the families. The relative mRNA expression levels of CFAP43 in patients 1 and 9 and the levels of CFAP44 in patient 5 were significantly lower than those in control sperm samples. Immunofluorescence analysis of CFAP43 showed the protein was absent in the sperm flagella of patients 1 and 9. Furthermore, two previously reported mutations of DNAH1 were also identified in another four (30.8%) patients. CONCLUSIONS: This study demonstrated that CFAP43 and CFAP44 mutations are important causes of MMAF in the Chinese population. These novel mutations broaden the spectrum of CFAP43 and CFAP44 mutations.

Patients with acephalic spermatozoa syndrome linked to SUN5 mutations have a favorable pregnancy outcome from ICSI.

STUDY QUESTION: Are Sad1 and UNC84 domain containing 5 (SUN5) mutations associated with the outcomes of ICSI in patients with acephalic spermatozoa syndrome (ASS)? SUMMARY ANSWER: Despite highly abnormal sperm morphology, ASS patients with SUN5 mutations have a favorable pregnancy outcome following ICSI. WHAT IS KNOWN ALREADY: ASS is a rare cause of infertility characterized by the production of a majority of headless spermatozoa, along with a small proportion of intact spermatozoa with an abnormal head-tail junction. Previous studies have demonstrated that SUN5 mutations may cause ASS. Several studies showed that ICSI could help patients with ASS father children. STUDY DESIGN, SIZE, DURATION: This retrospective cohort study included 11 infertile ASS males with SUN5 mutations. Five of them underwent five ICSI cycles. Their ICSI results were compared to men with ASS without SUN5 mutations (n = 3) and to men with multiple morphological abnormalities of the sperm flagella (MMAF) (n = 9). All ICSI treatments were completed between Jan 2011 and May 2017. PARTICIPANTS/MATERIALS, SETTING, METHODS: Sanger DNA sequencing was used to detect mutations in SUN5. Clinical and biological data were collected from patients at the fertility center. MAIN RESULTS AND THE ROLE OF CHANCE: Sanger sequencing validated 11 patients with SUN5 mutations. Three novel mutations in SUN5 (c.829C>T [p.Q277*]; c.1067G>A [p.R356H]; c.211+1 insGT [p.S71Cfs11*]) were identified in three patients. The rates of fertilization, good-quality embryos and pregnancy for five patients with SUN5 mutations following ICSI were 81.5%, 81.8% and 100%, respectively. The rates of fertilization and good-quality embryos in patients with MMAF were significantly lower compared with ASS patients (65.6 versus 82.4%, P = 0.039 and 53.6 versus 85.2%, P = 0.031, respectively). There were no differences in ICSI results between ASS patients with and without SUN5 mutations. LIMITATIONS, REASONS FOR CAUTION: Only a small number patients with SUN5 mutations was available because of its rare incidence. WIDER IMPLICATIONS OF THE FINDINGS: Patients with ASS can be effectively treated with ICSI. SUN5 mutations may be one of the genetic causes of ASS. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by the National Natural Science Foundation of China (81401251, 81370754, and 81170559), the Jiangsu Province Special Program of Medical Science (BL2012009, ZX201110, FXK201221) and a project funded by PAPD of the Priority Academic Program Development of Jiangsu High Education Institutions (JX10231802). None of the authors have any competing interests.

Novel mutations in PATL2 cause female infertility with oocyte germinal vesicle arrest.

STUDY QUESTION: Do PATL2 mutations account for female infertility with oocyte germinal vesicle (GV) arrest? SUMMARY ANSWER: Four of nine independent families with oocyte GV arrest were identified with biallelic PATL2 mutations, suggesting that these mutations may be responsible for oocyte maturation arrest in primary infertile women. WHAT IS KNOWN ALREADY: Recently, two independent studies have demonstrated that infertility in some women with oocyte maturation arrest at the GV stage was caused by biallelic mutations in PATL2. PATL2 encodes protein PAT1 homolog 2, an RNA-binding protein that may act as a translational repressor. STUDY DESIGN, SIZE, DURATION: In this study, nine unrelated primary infertile females presenting with oocyte GV arrest were recruited during the treatment of early rescue ICSI or ICSI from January 2013 to December 2016. PARTICIPANTS/MATERIALS, SETTING, METHODS: Genomic DNA was isolated from blood samples obtained from all nine affected individuals and all of their available family members. All the coding regions of PATL2 were sequenced by Sanger sequencing. The pathogenicity of the identified variants and their possible effects on the protein were evaluated in silico. MAIN RESULTS AND THE ROLE OF CHANCE: Five novel point mutations and one recurrent splicing mutation in PATL2 were identified in four of nine (44.4%) unrelated patients. We found a consanguineous family with a homozygous missense mutation in two affected sisters, and their fertile brother. There were no clear phenotypic differences in oocytes between the patient with the homozygous missense mutation, patients with nonsense mutations and undiagnosed patients. LARGE SCALE DATA: n/a. LIMITATIONS, REASONS FOR CAUTION: The function of PATL2 remains largely unknown. Both the exact pathogenic mechanism(s) of mutated PATL2 causing human oocyte maturation arrest and the strategies to overcome this condition should be further investigated in the future. WIDER IMPLICATIONS OF THE FINDINGS: According to our data, mutations in PATL2 account for 44.4% of the individuals with oocyte GV arrest. Our study further confirms that PATL2 is required for human oocyte maturation and female fertility, which indicates a potential prognostic value of testing for PATL2 mutations in primary infertile women with oocyte maturation arrest. STUDY FUNDING/COMPETING INTEREST(S): Natural Science Foundation of Anhui Province (1808085MH241), National Natural Science Foundation of China (81401251 and 81370757) and Central Guided Local Development of Science and Technology Special Fund (2016080802D114) supported this study. None of the authors have any competing interests.

Unraveling the Impact of the PROCA1 Mutation in Male Infertility: Incorporating Whole Exome Sequencing in Teratozoospermia Patients and Analyzing Proca1 Knockout Mice.

In the world, about 15% of couples are infertile, and nearly half of all infertility was caused by men. A large number of genetic mutations are thought to affect spermatogenesis by regulating acrosome formation. Here, we identified three patients harbouring the protein interacting with cyclin A1 (PROCA1) mutation by whole exome sequencing (WES) and Sanger sequencing among patients with predominantly acrosome-deficient teratozoospermia. However, the expression and roles of PROCA1 in infertile men remain unclear. We found that PROCA1 is predominantly expressed in the testis, where it is specifically localized to the acrosome of normal human sperm. Proca1 knockout (KO) mice were subsequently generated using CRISPR-Cas9 technology. However, Proca1 KO adult male mice were fertile, with testis-to-body weight ratios comparable to those of wild-type (WT) mice. Testicular tissue or sperm morphology were not significantly different in Proca1 KO mice compared to WT mice. Expression of the acrosome markers PNA and SP56 in the acrosome was comparable between Proca1 KO and WT mice. In summary, these findings suggested that the PROCA1 mutation identified in humans does not affect acrosome biogenesis in mice.