The Dazl (deleted in azoospermia-like) gene encodes an RNA-binding protein containing an RNA recognition motif (RRM) and a DAZ motif. Dazl is essential for gametogenesis in vertebrates. In this study, we report the cloning of Dazl cDNA from Cynops cyanurus. Ccdazl mRNA showed a germline-specific expression pattern as expected. Ccdazl expression gradually decreased during oogenesis, suggesting that it may be involved in oocyte development. Phylogenetic analysis revealed that the Ccdazl protein shares conserved motifs/domains with Dazl proteins from other species. Cloning of Ccdazl provides a new tool to carry out comparative studies of germ cell development in amphibians.

This study examined the effect of a cryoprotectant with and without pentoxifylline supplementation on the motility and viability of human testicular sperm, both before and after freezing. Testicular samples were obtained from 68 patients with azoospermia who came to the Andrology Service of West China Second University Hospital, Sichuan University, for testicular biopsies from December 2019 to April 2020. All patients were assigned randomly to two groups: experimental, whose testicular sperm were added to the cryoprotectant with pentoxifylline, and the control, whose testicular sperm were added to the cryoprotectant without pentoxifylline. Both groups used the same freezing and thawing methods. Testicular sperm motility in the experimental group was significantly higher than that of the control group, both before and after cryopreservation. The recovery rate of sperm motility in the experimental group was significantly higher than that of the control group. The percentage of samples with motile testicular sperm in the experimental group was significantly higher than that of the control group after thawing. Sperm viability was unchanged between the experimental and control groups, both before and after freezing. Overall, a pentoxifylline-supplemented cryoprotectant can significantly improve the motility of testicular sperm before and after cryopreservation.

The integrity of chromatin in the spermatozoon is essential for reproductive outcome. The aim of this study was to evaluate the most effective and cost-effective method to reduce the percentage of spermatozoa with defects in chromatin decondensation for use in assisted reproductive technologies (ART) procedures. Sperm samples from 15 sub-fertile males were examined at CFA Naples to determine the sperm decondensation index (SDI), using the aniline blue test, before and after preparation, comparing density gradients with two different swim-up approaches. All three techniques led to a reduction in decondensed spermatozoa with no statistical difference (P > 0.05) between the control and the treated sperm. In contrast, we found a highly significant decrease in SDI (P < 0.01) after the two swim-up methods in all the samples, confirming the efficacy of these methods in lowering the percentage of chromatin compaction damage. There was no statistical difference between the two swim-up methods, however swim-up from the pellet led to improved count, motility and the percentage of normal condensed spermatozoa. We suggest that swim-up from the pellet be used in ART on sub-fertile males, both to reduce cell stress by multiple centrifugation and improve the recovery rate of mature spermatozoa.

Iksookimia longicorpa and Cobitis hankugensis are two species of fish distributed only on the Korean Peninsula. They have a unique reproductive ecology that naturally hybridizes into three widely known unisexual types, maintaining populations of almost all females. In this study, the fine structure of the micropyles of I. longicorpa, C. hankugensis and their hybrids was analyzed to find out how egg–sperm interaction, a common interspecies isolation mechanism, is possible between heterogeneous species. Analysis of 30 eggs from five females of each species revealed that all had one funnel-shaped micropylar region and a manhole-shaped micropyle canal. With the exception of C. hankugensis, which had no spiral grooves or ridges, the rest had counterclockwise spiral grooves and ridges on the micropylar region. All five species, however, showed identical groove patterns for the micropyle canal. The egg size was the largest in HL (one from the C. hankugensis locus with one from the I. longicorpa locus) and the smallest in C. hankugensis. In the hybrids, the HL type had the largest egg and HHL (two from the C. hankugensis locus with one from the I. longicorpa locus) type the smallest. For the diameter of the micropylar region and micropyle canal, the diploid I. longicorpa, C. hankugensis and HL were smaller than those of the triploid. In addition, as the ratio of the canal diameter to the eggs was lower in I. longicorpa than in C. hankugensis, it was confirmed that I. longicorpa has a relatively small micropyle canal compared with C. hankugensis.

Methomyl is a broad-spectrum carbamate insecticide that has a variety of toxic effects on humans and animals. However, there have been no studies on the toxicity of methomyl in female mammalian oocytes. This study investigated the toxic effects of environmental oestrogen methomyl exposure on mouse oocyte maturation and its possible mechanisms. Our results indicated that methomyl exposure inhibited polar body extrusion in mouse oocytes. Compared with that in the control group, in the methomyl treatment group, superoxide anion free radicals in oocytes were significantly increased. In addition, the mitochondrial membrane potential of metaphase II stage oocytes in the methomyl treatment group was significantly decreased, resulting in reduced mouse oocyte quality. After 8.5 h of exposure to methomyl, metaphase I stage mouse oocytes displayed an abnormal spindle morphology. mRNA expression of the pro-apoptotic genes Bax and Caspase-3 in methomyl-treated oocytes increased, which confirmed the apoptosis. Collectively, our results indicated that mouse oocyte maturation is defective after methomyl treatment at least through disruption of spindle morphology, mitochondrial function and by induction of oxidative stress.

The objective of this study was to investigate the effects of adding β-mercaptoethanol (βME) to culture medium of bovine in vitro-produced (IVP) embryos prior to or after vitrification on embryo development and cryotolerance. In Experiment I, Day-7 IVP blastocysts were vitrified and, after warming, cultured in medium containing 0, 50 or 100 μM βME for 72 h. Embryos cultured in 100 μM βME attained higher hatching rates (66.7%) than those culture in 0 (47.7%) and 50 (52.4%) μM βME. In Experiment II, IVP embryos were in vitro-cultured (IVC) to the blastocyst stage in 0 (control) or 100 μM βME, followed by vitrification. After warming, embryos were cultured for 72 h (post-warming culture, PWC) in 0 (control) or 100 μM βME, in a 2 × 2 factorial design: (i) CTRL–CTRL, control IVC and control PWC; (ii) CTRL–βME, control IVC and βME-supplemented PWC; (iii) βME–CTRL, βME-supplemented IVC and control PWC; or (iv) βME–βME, βME-supplemented IVC and βME-supplemented PWC. βME during IVC reduced embryo development (28.0% vs. 43.8%) but, following vitrification, higher re-expansion rates were seen in βME–CTRL (84.0%) and βME–βME (87.5%) than in CTRL–CTRL (71.0%) and CTRL–βME (73.1%). Hatching rates were higher in CTRL–βME (58.1%) and βME–βME (63.8%) than in CTRL–CTRL (36.6%) and βME–CTRL (42.0%). Total cell number in hatched blastocysts was higher in βME–βME (181.2 ± 7.4 cells) than CTRL–CTRL (139.0 ± 9.9 cells). Adding βME to the IVC medium reduced development but increased cryotolerance, whereas adding βME to the PWC medium improved embryo survival, hatching rates, and total cell numbers.

Toll-like receptor 4 (TLR4) is best known for its role in bacteria-produced lipopolysaccharide recognition. Regarding female reproduction, TLR4 is expressed by murine cumulus cells and participates in ovulation and in cumulus–oocyte complex (COC) expansion, maternal–fetal interaction and preterm labour. Despite these facts, the role of TLR4 in ovarian physiology is not fully understood. Therefore, the aim of the present study was to investigate the effects of TLR4 genetic ablation on mice folliculogenesis and female fertility, through analysis of reproductive crosses, ovarian responsiveness and follicular quantification in TLR4−/− (n = 94) and C57BL/6 mice [wild type (WT), n = 102]. TLR4-deficient pairs showed a reduced number of pups per litter (P = 0.037) compared with WT. TLR4−/− mice presented more primordial, primary, secondary and antral follicles (P < 0.001), however there was no difference in estrous cyclicity (P > 0.05). A lower (P = 0.006) number of COC was recovered from TLR4−/− mice oviducts after superovulation, and in heterozygous pairs, TLR4−/− females also showed a reduction in the pregnancy rate and in the number of fetuses per uterus (P = 0.007) when compared with WT. Altogether, these data suggest that TLR4 plays a role in the regulation of murine folliculogenesis and in determining ovarian endowment. TLR4 deficiency may affect ovulation and pregnancy rates, potentially decreasing fertility, therefore the potential side effects of its blockade have to be carefully investigated.

To enhance the developmental competency of murine ovarian follicles cultured in vitro, C-type natriuretic peptide (CNP) was supplemented in the culture system. Although the mechanism is not fully elucidated, it was reported that the effect of CNP supplementation was mediated by increased cyclic guanosine monophosphate (cGMP). In the present study, cGMP levels in media for murine preantral follicle culture were compared both between a control group without CNP supplementation and an experimental group with CNP supplementation and between days in each group. In addition, follicle growth patterns and oocyte maturity were assessed and compared between the two groups. Results demonstrated that along with in vitro culture, cGMP levels increased (P < 0.05) both in the control group and the experimental group, whereas cGMP levels were not significantly different between the two groups on the same day of in vitro culture (P > 0.05). The oocyte’s maturity was superior in the experimental group compared with the control group (P < 0.05). As ovarian follicles grew three-dimensionally in the experimental group but were flattened in the control group, CNP might improve oocyte maturity through maintaining the three-dimensional architecture of the ovarian follicle because of increased transzonal projections (TZP) and functional gap junctions between oocyte and surrounding granulosa cells.

Domestic cat embryos generated by in vitro fertilization (IVF) and cultured without the zona pellucida have a reduced implantation capacity after embryo transfer at the blastocyst stage. The objective of this study was to evaluate the expression of trophectoderm markers in domestic cat blastocysts cultured without the zona pellucida. Two experimental groups were selected: (1) domestic cat embryos generated by IVF and cultured in vitro normally (zona intact group, ZI); and (2) domestic cat embryos generated by IVF and cultured in vitro without a zona pellucida (zona-free group, ZF). In the ZF group, the zona pellucida of the presumptive zygote was removed and these were cultured using the well of the well (WOW) system. In vitro culture was carried out for 7 days. The cleavage, morula and blastocyst rates were estimated. Finally, the relative expression levels of the trophectoderm markers TEAD4, YAP1, CDX2 and EOMES, the cell adhesion marker E-cadherin and the apoptosis marker CASP3 were evaluated by RT-qPCR in the blastocysts. The Wilcoxon test was used to evaluate differences (P < 0.05). No differences were observed in the cleavage, morula and blastocyst rates between the ZF and ZI groups. No differences were found in the expression of TEAD4, CDX2, E-cadherin and CASP3 between groups. The expression of YAP1 and EOMES was higher in ZF blastocysts than in ZI blastocysts. In conclusion, the in vitro culture without the zona pellucida generates an overexpression of YAP1 and EOMES in the domestic cat blastocysts. More studies are needed to confirm if this overexpression might affect in vivo development.

We compared the pregnancy and live birth rates following transfer of early-stage embryos or blastocysts produced by somatic cell nuclear transfer using in vitro-matured oocytes. In total 102 ovaries were collected from dromedary camels at a local abattoir; from these 1048 cumulus–oocytes complexes (COCs) were aspirated and cultured for 42 h in a commercial maturation medium. Metaphase II oocytes were subjected to nuclear transfer. Somatic cell nuclear transfer-derived embryos were cultured in a commercial embryo medium for 2 or 7 days. Next, 71 early-stage embryos were surgically transferred to the left fallopian tube of 28 recipients and 47 blastocysts were transferred to the left uterine horn of 26 recipients. Early pregnancy was detected by serum progesterone (P4), and pregnancy was confirmed using ultrasonography on days 30 and 90 after embryo transfer. Pregnancy rate based on P4 level was 17.86% (5/28) and 11.54% (3/26) for early-stage embryo and blastocyst transfer, respectively. In the early-stage embryo group, out of five recipients, one recipient had lost the pregnancy by the first ultrasonography on day 30; two other recipients aborted at 14 and 24 weeks, and two recipients gave live births. In the blastocyst group, out of three recipients, one lost the pregnancy at an early stage and two recipients gave live births. Therefore, for dromedary camels, we recommend transvaginal blastocyst transfer from the standpoint of the pregnancy and live birth rate, ease of the transfer procedure, and comfort and safety of the recipients.

The enzyme 5,10-methylenetetrahydrofolate reductase (MTHFR) links the folate cycle that produces one-carbon units with the methionine cycle that converts these into S-adenosylmethionine (SAM), the universal methyl donor for almost all methyltransferases. Previously, MTHFR has been shown to be regulated by phosphorylation, which suppresses its activity. SAM levels have been shown to increase substantially soon after initiation of meiotic maturation of the mouse germinal vesicle (GV) stage oocyte and then decrease back to their original low level in mature second meiotic metaphase (MII) eggs. As MTHFR controls the entry of one-carbon units into the methionine cycle, it is a candidate regulator of the SAM levels in oocytes and eggs. Mthfr transcripts are expressed in mouse oocytes and preimplantation embryos and MTHFR protein is present at each stage. In mature MII eggs, the apparent molecular weight of MTHFR was increased compared with GV oocytes, which we hypothesized was due to increased phosphorylation. The increase in apparent molecular weight was reversed by treatment with lambda protein phosphatase (LPP), indicating that MTHFR is phosphorylated in MII eggs. In contrast, LPP had no effect on MTHFR from GV oocytes, 2-cell embryos, or blastocysts. MTHFR was progressively phosphorylated after initiation of meiotic maturation, reaching maximal levels in MII eggs before decreasing again after egg activation. As phosphorylation suppresses MTHFR activity, it is predicted that MTHFR becomes inactive during meiotic maturation and is minimally active in MII eggs, which is consistent with the reported changes in SAM levels during mouse oocyte maturation.

In vitro culture of ovarian tissue containing primordial follicles is an important tool to study the initiation of follicular populations and to develop efficient culture systems to support in vitro follicle growth. Considering that in vitro culture favours oxidative stress, it is very important to supplement culture medium with antioxidant substances such as Aloe vera extract. This study aims to evaluate the effects of different concentrations of Aloe vera on the distribution of collagen fibres in the extracellular matrix, follicular activation, development and survival in bovine ovarian cortical tissues cultured in vitro, as well as on expression of mRNAs for antioxidant enzymes [superoxide dismutase (SOD), catalase (CAT), peroxiredoxin 6 (PRDX6) and glutathione peroxidase 1 (GPX1)]. To this end, ovarian cortical tissues were cultured for 6 days in α-MEM alone or supplemented with different concentrations of Aloe vera extract (1.0, 5.0, 10.0 or 50.0%). After culture, fragments were fixed and processed histologically to evaluate follicular morphology and activation, as well as the extracellular matrix by staining with picrosirius red. The levels of mRNA for SOD, CAT, PRDX6 and GPX1 in cultured ovarian tissues were evaluated by real-time polymerase chain reaction (PCR). Ovarian tissues cultured with 10.0 or 50.0% Aloe vera had higher percentages of collagen fibres than tissues cultured in control medium. A significant increase in developing follicles was observed in ovarian tissues cultured in α-MEM alone or supplemented with 10% Aloe vera when compared with fresh control or tissues cultured with 1.0% Aloe vera. Presence of Aloe vera did not influence the percentage of morphologically normal follicles when compared with control medium. Ovarian tissues cultured with 50.0% Aloe vera had higher percentages of morphologically normal follicles than those cultured with 10.0% Aloe vera. Furthermore, 10% Aloe vera significantly increased mRNA levels for PRDX6. In conclusion, 10.0% Aloe vera improves extracellular matrix distribution in cultured tissues and increases the expression of mRNA for PRDX6 after 6 days in vitro.

Congenital domestic absence of vas deferens (CBAVD) is a common factor in male infertility, and percutaneous epididymal sperm aspiration (PESA) combined with intracytoplasmic sperm injection (ICSI) is a primary clinical treatment, but the effect of the sperm obtained on pregnancy outcome remains to be explored. This study aimed to investigate the relationship between sperm motility with clinical outcome of PESA–ICSI in infertile males with CBAVD. A cohort of 110 couples was enrolled. In total, 76 infertile males were included in the high motility group, while the remaining 34 males were placed in the low motility group. Clinical pregnancy, embryo implantation rate and live birth rate were included as the primary outcome. After all follow-ups, we found that the high motility group achieved higher normal fertilization rates, cleavage rates, transplantable embryo rates and high-quality embryo rates than those in low motility group (normal fertilization rate, 78.2 ± 11.7% vs. 70.5 ± 10.2%, P = 0.003; cleavage rate, 97.1 ± 2.9% vs. 92.3 ± 3.0%, P = 0.000; transplantable embryo rate, 66.8 ± 14.9% vs. 58.6 ± 12.6%, P = 0.009 and high-quality embryo rate, 49.9 ± 10.5% vs. 40.5 ± 11.2%, P = 0.000). Additionally, compared with the low motility group, the clinical pregnancy rates, embryo implantation rates, and live birth rates in the high motility group were significantly increased (pregnancy rate, 61.8% vs. 26.5%, P = 0.009; embryo implantation rate, 36.5% vs. 18.0%, P = 0.044; live birth rate, 55.3% vs. 17.6%, P = 0.000). We concluded that the motility of sperm obtained by PESA affected the clinical outcome of ICSI in infertile males with CBAVD.

Using the KIDScoreTM D3 (KID3) scoring system, day 3 embryos observed by time-lapse imaging (TLI) were scored to explore the predictive value of the KID scoring system on the developmental potential of embryos. The kinetic parameters of 477 normal fertilized embryos from 77 patients who underwent TLI in our hospital from January 2019 to June 2020 were evaluated by KID3, and the embryos were divided into five groups according to the scores for retrospective analysis of blastocyst formation. Additionally, the high-quality blastocyst formation rate, pregnancy rate and early abortion rate were analyzed via KID3 and traditional morphological assessments, and comparisons of differences among different ages were also performed. In the KID3 estimate, the blastocyst or high-quality blastocyst formation rate in the score 5 group was markedly higher than that in the score 1–4 groups. Blastocyst or high-quality blastocyst formation rates in the A group (the results of two evaluation tools indicated they were excellent embryos) and the B group (KID3: excellent embryos, traditional evaluation: not excellent embryos) were evidently increased in comparison with the C or D group (KID3: not excellent embryos, traditional evaluation: excellent embryo or not, respectively). Furthermore, the percentages of score 5 embryos, blastocyst and high-quality blastocyst formation rates for patients ≥ 35 years old were markedly decreased compared with those for patients < 34 years old, while the trends of nondiploid cleavage, multinucleation and asymmetric division were the opposite. Collectively, the KID3 scoring system may be a promising predictive tool for screening embryos with better developmental potential.

Our research question was to evaluate the chromosome concordance of trophectoderm (TE) biopsy with noninvasive chromosome screening (NICS) using embryo culture medium renewed twice on Day 3 (D3) and Day 4 (D4). In this study, we evaluated 64 cycles with 223 biopsied blastocysts. These were categorized into two groups based on replacing embryo culture medium on D3 (control group) or on D3 and D4 (experimental group). The fundamental characteristics and main outcomes were compared. The concordance rates of NICS results with TE biopsy were determined according to next generation sequencing results. In total, 103 experimental and 120 control embryo cultures were collected, and the euploid status was analyzed using NICS technology. The overall concordance rates with TE biopsy of the experimental and control groups were 0.86 and 0.75, respectively. Statistically significant difference was found between the two groups. An additional medium renewal of the D4 embryo culture can improve the concordance of NICS with TE biopsy.

It has been documented that the inefficacy of round spermatid injection (ROSI) might be caused by abnormal epigenetic modifications. Therefore, this study aimed to evaluate the effect of trichostatin A (TSA) as an epigenetic modifier of preimplantation embryo development in activated ROSI oocytes. Matured oocytes were collected from superovulated female mice. Testes were placed in human tubal fluid medium and masses were then cut into small pieces to disperse spermatogenic cells. Round spermatids were treated with TSA and subsequently injected into oocytes. The expression level of the development-related genes including Oct4, Sox2, Nanog, Dnmt and Hdac transcripts were evaluated using qRT-PCR. Immunohistochemistry was performed to confirm the presence of Oct-4 protein at the blastocyst stage. There was no statistically significant difference in fertilization rate following ROSI/+TSA compared with the non-treated ROSI and intracytoplasmic sperm injection (ICSI) groups. Importantly, TSA treatment increased blastocyst formation from 38% in non-treated ROSI to 68%. The relative expression level of developmentally related genes increased and Dnmt transcripts decreased in ROSI/+TSA-derived embryos, similar to the expression levels observed in the ICSI-derived embryos. In conclusion, our results indicate that spermatid treatment with TSA prior to ROSI would increase the success rate of development to the blastocyst stage and proportion of pluripotent cells.

This study was performed to improve production efficiency at the level of recipient pig and donor nuclei of transgenic cloned pigs used for xenotransplantation. To generate transgenic pigs, human endothelial protein C receptor (hEPCR) and human thrombomodulin (hTM) genes were introduced using the F2A expression vector into GalT–/–/hCD55+ porcine neonatal ear fibroblasts used as donor cells and cloned embryos were transferred to the sows and gilts. Cloned fetal kidney cells were also used as donor cells for recloning to increase production efficiency. Pregnancy and parturition rates after embryo transfer and preimplantation developmental competence were compared between cloned embryos derived from adult and fetal cells. Significantly higher parturition rates were shown in the group of sows (50.0 vs. 4.1%), natural oestrus (20.8 vs. 0%), and ovulated ovary (16.7 vs. 5.6%) compared with gilt, induced and non-ovulated, respectively (P < 0.05). When using gilts as recipients, final parturitions occurred in only the fetal cell groups and significantly higher blastocyst rates (15.1% vs. 21.3%) were seen (P < 0.05). Additionally, gene expression levels related to pluripotency were significantly higher in the fetal cell group (P < 0.05). In conclusion, sows can be recommended as recipients due to their higher efficiency in the generation of transgenic cloned pigs and cloned fetal cells also can be recommended as donor cells through correct nuclear reprogramming.

Oocytes eligible for intracytoplasmic sperm injection (ICSI) are those that have progressed through meiosis to metaphase 2 (MII). The remaining delayed mature oocytes can be injected, aiming to achieve more embryos and a better chance to conceive. We aimed to assess the outcome of delayed matured oocytes, derived from either germinal vesicles or metaphase 1 (MI), that reached maturity (MII) 24 h following retrieval. The study population consisted of 362 women who underwent 476 IVF cycles. While fertilization rates were comparable between the sibling delayed mature oocyte group compared with injection on day 0 group (58.4% vs 62%, respectively, P = 0.07), the top-quality embryo rate per injected MII day 0 oocyte was significantly higher compared with day 1 injected oocyte (57.5% vs 43.9% respectively, P < 0.001). Moreover, following fresh transfer of embryos derived from delayed mature oocytes, implantation rate and the clinical pregnancy (CPR) and live-birth rates (LBR) per transfer were 3.9%, 3.3% and 1.6% respectively. When considering the following thawed embryo transfer cycles, implantation, pregnancy and LBR were non-significantly higher (10%, 8.3% and 8.3%, respectively). Although clinical outcomes are significantly lower when using embryos derived from delayed mature oocyte to mature day 0 oocytes, the additional embryos derived from delayed mature oocytes might contribute to the embryo cohort and increase the cumulative live-birth rate per retrieval. Moreover, the embryos derived from delayed mature oocyte favour a transfer in a frozen–thawed cycle rather than in a fresh cycle.

To explore the effect of lncRNA TINCR on the biological behaviours of trophoblasts, we detected and analyzed the expression of terminal differentiation-induced non-protein coding RNA (TINCR) in the placenta tissues of pre-eclamptic and non-pre-eclamptic pregnant women. The gain- and loss-of-function of TINCR was performed to examine the proliferation, migration and invasion abilities of Htr-8/Svneo cells. The levels of epithelial–mesenchymal transition (EMT)-related proteins, cyclin and Wnt/β-catenin pathway were detected. High expression of lncRNA TINCR appeared in placental tissues of patients with pre-eclampsia. The proliferation, invasion and migration of Htr-8/Svneo cells were promoted by TINCR downregulation; the cells were transited from G0/G1 to S phase; and EMT was promoted and the Wnt/β-catenin pathway was activated. In summary, the downregulation of lncRNA TINCR activated the Wnt/β-catenin pathway and promoted the proliferation, invasion and migration of Htr-8/Svneo cells. This study may provide a theoretical basis for treatment of patients with pre-eclampsia.

Polycystic ovarian syndrome (PCOS) is a chronic hormonal turmoil that is demonstrated in 2.2−27% of women of pre-menopausal age. This disease is a complex multigenic disorder that results from the interaction between excess androgen expression, genetic susceptibility and environmental influences. PCOS is associated with 40% of female infertility and endometrial cancer. The WNT/β-catenin signalling transduction pathway regulates aspects of cell proliferation, migration and cell fate determination in the tissue along with early embryonic development and controls the proper activation of the female reproductive system, along with regulating hormonal activity in ovarian granulosa cells. In the current study, we investigated the expression profiles of WNT/β-catenin signalling pathway genes (AXIN2, FZD4, TCF4, WNT3, WNT4, WNT5A, WNT7A, WNT1, APC, GSK3B and β-catenin) in a total of 13 oocyte samples. Seven of these samples were from polycystic women and six were from healthy women. The results of this study displayed the absence of expression of AXIN2, FZD4, TCF4, WNT5A, WNT3, WNT4 and WNT7A genes in ovaries from women with PCOS and from healthy women. While APC and β-catenin expression levels were similar in the oocytes of both patients and controls, conversely, WNT1 and GSK3β genes both showed elevated expression in the oocytes of patients with PCOS, therefore suggesting an association between aberrant expression of WNT1 and GSK3β and the pathogenesis of PCOS. The observations of the current study could be helpful to provide evidence regarding the pathogenesis of PCOS and its treatment.