Phosphodiesterase 8B gene polymorphism in women with recurrent miscarriage: a retrospective case control study

Impact of rs2046045 SNP in PDE8B on TSH Levels: Insights into Genetic Susceptibility to Hypothyroidism

Hypothyroidism is the most prevalent thyroid disorder and leads to adverse effects on the human body. Serum thyroid stimulating hormone (TSH) values have been related to polymorphisms in multiple genes that may be involved in the regulation of thyroid function. The single nucleotide polymorphism (SNP) rs2046045 is situated in the intron region of the phosphodiesterase 8B (PDE8B) gene, which encodes a high-affinity cyclic adenosine monophosphate (cAMP)-specific phosphodiesterase widely expressed in thyroid tissue. The principal goal of the present study was to investigate the association between the SNP rs2046045 of the PDE8B gene and hypothyroidism. The study was designed as a case-control study, and a total of 160 hypothyroid and 160 healthy controls were involved. Blood samples were drawn from each individual, and deoxyribonuleic acid (DNA) was separated with a suitable DNA isolation kit. For genotyping, the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique was employed. The IBM Statistical Package for Social Sciences (SPSS) 25.0 was utilized to analyze the statistical data. Age differences between the patients and controls were not observed in the present study. The genotype frequency of homozygous wild type (TT), homozygous mutate type (GG), and heterozygous (GT) was 45%, 2.5%, and 52.5%, respectively, in control subjects and 27.5%, 11.25%, and 61.25%, respectively, in cases, and showed a significant difference (p = 0.0002). The minor G allele frequency is elevated in hypothyroid patients as compared to healthy control subjects (41.87% vs. 28.75%), p = 0.0005. The presence of the mutant allele G of rs2046045 in the PDE8B gene correlates with elevated serum TSH levels in hypothyroid patients.

Association between the rs3802201 polymorphism of the lncRNA MIR2052HG gene and the risk of recurrent miscarriage in a Southern Chinese population

BACKGROUND

Plenty of studies have indicated that some genetic polymorphisms of the breast cancer which associated with its susceptibility may also be related to the susceptibility of abortion. MIR2052HG plays an important role in the onset and progression of breast cancer by maintaining the level of ERα, but to the best of our knowledge, the correlation between risk of recurrent abortion and MIR2052HG rs3802201 C>G polymorphism is still unclear. Therefore, we conducted this case-control study to investigate whether MIR2052HG rs3802201 C>G polymorphism is associated with susceptibility of recurrent miscarriage (RM).

METHODS

We recruited 392 healthy controls and 248 patients with RM to process this research, the participants were all from southern China, and genotyping was performed by TaqMan method.

RESULTS

Our results showed that there was no evidence indicates the MIR2052HG rs3802201 C>G is related to RM (CG and CC: adjusted OR = 0.970, 95% CI = 0.694-1.355, p = 0.8577; GG and CC: adjusted OR = 0.743, 95% CI = 0.416-1.330, p = 0.3174; dominant model: adjusted OR = 0.925, 95% CI = 0.672-1.272, p = 0.6298; recessive model: adjusted OR = 0.751, 95% CI = 0.430-1.321, p = 0.3233).

CONCLUSION

We verified that the MIR2052HG rs3802201 C>G allele might be uncorrelated to the RM risk, but these findings require further validation in multicenter studies with larger sample size and different ethnicities.

Phosphodiesterase 8B Polymorphism rs4704397 Is Associated with Infertility in Subclinical Hypothyroid Females: A Case-Control Study

BACKGROUND

Subclinical hypothyroidism (SCH) remains largely unnoticed as a major cause of infertility due to asymptomatic. Polymorphisms of phosphodiesterase 8B gene (PDE8B) have been linked with various diseases, including female infertility. Hence, we aimed to study prevalence of SCH, in infertile females, explore association of PDE8B rs4704397 A/G and rs6885099 G/A polymorphisms with infertility in females suffering from SCH and genotype-phenotype correlation of the polymorphisms with thyroid stimulating hormone (TSH) levels in Gujarat population.

MATERIALS AND METHODS

In this retrospective study, TSH level was estimated from plasma of 230 infertile and 100 control females by enzyme-linked fluorescence immunoassay (ELFA) to find out the prevalence of SCH. Further, based on TSH levels, thyroid function test (TFT) was performed in controls and infertile females with subclinical hypothyroidism (IF-SCH). PDE8B rs4704397 and rs6885099 polymorphisms were genotyped by PCR-RFLP and ARMS-PCR, respectively in 74 controls and 60 IF-SCH females.

RESULTS

We observed i. significantly high prevalence of SCH (32%) in the infertile females, ii. significantly lower frequency of 'G' allele (P=0.006), while the frequency of 'A' allele (P<0.0001) was higher in IFSCH females, compared to the controls, for rs4704397 A/G SNP, iii. no significant difference in the genotype (P=0.214; OR=2.51; CI=0.74-8.42) and the allele frequency (P=0.129; OR=1.51; CI=0.92-2.47) of rs6885099 G/A SNP, iv) low linkage disequilibrium for the polymorphisms, v. significantly higher frequency of 'AA' haplotype (P=0.0001; OR=3.84; CI=1.86-8.01),while the 'GG' haplotype (P=0.0023; OR=0.33; CI=0.16-0.69) was significantly lower in IF-SCH females and vi. no significant difference in the TSH level of IF-SCH females with respect to the genotypes.

CONCLUSION

The present study reports an association of PDE8B rs4704397 polymorphism with infertility in SCH females. The study categorically shows a higher prevalence of SCH in infertile females of Gujarat and advocates the importance of screening for SCH in infertility management.

Levels of caspase-3 and histidine-rich glycoprotein in the embryo secretome as biomarkers of good-quality day-2 embryos and high-quality blastocysts

Morphological assessment at defined developmental stages is the most important method to select viable embryos for transfer and cryopreservation. Timing of different developmental stages in embryo development has been shown to correlate with its potential to develop into a blastocyst. However, improvements in pregnancy rates by using time-lapse techniques have been difficult to validate scientifically. Therefore, there is a need for new methods, preferably non-invasive methods based on metabolomics, genomics and proteomics, to improve the evaluation of embryo quality even further. The aim of this study was to investigate if different levels of caspase-3 and histidine-rich glycoprotein (HRG), secreted by the embryo into the culture media, can be used as biomarkers of embryo quality. In this study, a total of 334 samples of culture media were collected from in vitro fertilization (IVF) treatments at three different clinics. Protein analysis of the culture media was performed using multiplex proximity extension protein analysis to detect levels of caspase-3 and HRG in the embryo secretome. Protein levels were compared in secretome samples from high- and low-quality blastocysts and embryos that became arrested during development. Correlation between protein levels and time to morula formation was also analyzed. Furthermore, protein levels in secretomes from day-2 cultured embryos were compared on the basis of whether or not pregnancy was achieved. The results showed that caspase-3 levels were lower in secretomes from high-quality vs. low-quality blastocysts and those that became arrested (p ≤ 0.05 for both). In addition, higher HRG levels correlated with a shorter time to morula formation (p ≤ 0.001). Caspase-3 levels were also lower in secretomes from day-2 cultured embryos resulting in a pregnancy vs. those that did not (p ≤ 0.05). Furthermore, it was shown that caspase-3 might be used as a marker for predicting potential success rate after transfer of day-2 cultured embryos, where a caspase-3 cutoff level of 0.02 gave a prediction probability of 68% (p = 0.038). In conclusion, in future prediction models, levels of caspase-3 and HRG might be used as potential markers of embryo quality, and secreted caspase-3 levels could to some extent predict the outcome after transfer of day-2 cultured embryos.

Genetic determination of the hypothalamic-pituitary-thyroid axis: where do we stand?

For a long time it has been known that both hypo- and hyperthyroidism are associated with an increased risk of morbidity and mortality. In recent years, it has also become clear that minor variations in thyroid function, including subclinical dysfunction and variation in thyroid function within the reference range, can have important effects on clinical endpoints, such as bone mineral density, depression, metabolic syndrome, and cardiovascular mortality. Serum thyroid parameters show substantial interindividual variability, whereas the intraindividual variability lies within a narrow range. This suggests that every individual has a unique hypothalamus-pituitary-thyroid axis setpoint that is mainly determined by genetic factors, and this heritability has been estimated to be 40-60%. Various mutations in thyroid hormone pathway genes have been identified in persons with thyroid dysfunction or altered thyroid function tests. Because these causes are rare, many candidate gene and linkage studies have been performed over the years to identify more common variants (polymorphisms) associated with thyroid (dys)function, but only a limited number of consistent associations have been found. However, in the past 5 years, advances in genetic research have led to the identification of a large number of new candidate genes. In this review, we provide an overview of the current knowledge about the polygenic basis of thyroid (dys)function. This includes new candidate genes identified by genome-wide approaches, what insights these genes provide into the genetic basis of thyroid (dys)function, and which new techniques will help to further decipher the genetic basis of thyroid (dys)function in the near future.

Association between trefoil factor 3 gene variants and idiopathic recurrent spontaneous abortion

Trefoil factor 3 (TFF3) gene is an inflammatory mediator expressed in human endometrium during the window of implantation. The aim of this study was to evaluate the possible genetic association of TFF3 variants in recurrent spontaneous abortion. Women with a history of recurrent spontaneous abortion (n = 164) and healthy pregnant women (n = 143) were genotyped for five TFF3 polymorphisms (rs225439 G/A, rs533093 C/T, rs225361 A/G, rs11701143 T/C and rs77436142 G/C). In addition, haplotypes formed within the gene were analysed. Within the recurrent spontaneous abortion group, women who at some point had given birth and childless women had 4.19 ± 1.75 and 5.34 ± 3.42 consecutive spontaneous abortions, respectively. Women who had experience recurrent spontaneous abortions had a lower allele frequency of the rs11701143 promoter region minor C allele compared with fertile women (0.02 versus 0.05, P = 0.015). Patients with rs225361 AG genotype had significantly more successful pregnancies before spontaneous abortion than those with homozygous AA and GG genotypes (P = 0.014). No significant differences in haplotype frequencies between patients and controls were detected. Possible genetic risk factors identified that might contribute to the pathogenesis of idiopathic recurrent spontaneous abortion were TFF3 gene variants.