[Analysis of Risk Factors for Recurrent Pregnancy Loss in Patients Undergoing in vitro Fertilization-Embryo Transfer]. / 体外受精-èƒšèƒŽç§»æ¤æ‚£è€ ä¸­åå¤å¦Šå¨ ä¸¢å¤±çš„å±é™©å› ç´ åˆ†æž.

Objective: Recurrent pregnancy loss (RPL) presents a formidable challenge for individuals undergoing in vitro fertilization-embryo transfer (IVF-ET), forming both a clinical dilemma and a focal point for scientific inquiry. This study endeavors to investigate the intricate interplay between clinical features, such as age, body mass index (BMI), and waist-to-hip ratio (WHR), and routine laboratory parameters, including sex hormones, blood composition, liver and thyroid functions, thyroid antibodies, and coagulation indicators, in RPL patients undergoing IVF-ET. By meticulously analyzing these variables, we aim to uncover the latent risk factors predisposing individuals to RPL. Identifying potential factors such as advanced maternal age, obesity, and insulin resistance will provide clinicians with vital insights and empirical evidence to strengthen preventive strategies aimed at reducing miscarriage recurrence. Methods: This retrospective case-controlled study included RPL patients who underwent IVF-ET treatment at Sun Yat-sen Memorial Hospital, Sun Yat-sen University, between January 2012 and March 2021 as the case cohort, compared with women receiving assisted reproductive treatment due to male infertility as the control cohort. The fasting peripheral blood was collected 5 days before the first menstrual cycle at least 12 weeks after the last abortion. The clinical characteristics and relevant laboratory indexes of the two groups were compared. Employing both univariate and multivariate logistic regression analyses, we sought to unearth potential high-risk factors underlying RPL. Additionally, a linear trend analysis was conducted to assess the linear relationship between total testosterone (TT) levels and the number of miscarriages. Results: In contrast to the control cohort, the RPL cohort exhibited significant increases in age, BMI, and WHR (P<0.05). Notably, TT levels were markedly lower in the RPL cohort (P=0.022), while no significant differences were observed between the two groups concerning basal follicle-stimulating hormone, luteinizing hormone, estradiol, progesterone, prolactin levels, and anti-Müllerian hormone levels (P>0.05). Moreover, fasting insulin (FINS) levels and HOMA-IR index were notably elevated in the RPL cohort relative to the control cohort (P<0.001), although no significant differences were observed in fasting blood glucose levels (P>0.05). Furthermore, the neutrophil (NEU) count and NEU-to-lymphocyte ratio were notably higher in the RPL cohort (P<0.01). Univariate logistic regression analysis identified several factors, including age≥35 years old, BMI≥25 kg/m2, WHR>0.8, FINS>10 mU/L, HOMA-IR>2.14, NEU count>6.3×109 L－1, and an elevated NEU/lymphocyte ratio (NLR), as significantly increasing the risk of RPL (P<0.05). Although TT levels were within the normal range for both cohorts, higher TT levels were associated with a diminished RPL risk (odds ratio [OR]=0.67, 95% confidence interval [CI]: 0.510-0.890, P=0.005). After adjustments for confounding factors, age≥35 years old (OR=1.91, 95% CI: 1.06-3.43), WHR>0.8 (OR=2.30, 95% CI: 1.26-4.19), and FINS>10 mU/L (OR=4.50, 95% CI: 1.30-15.56) emerged as potent risk factors for RPL (P<0.05). Conversely, higher TT levels were associated with a reduced RPL risk (OR=0.59, 95% CI: 0.38-0.93, P=0.023). Furthermore, the linear trend analysis unveiled a discernible linear association between TT levels and the number of miscarriages (P trend=0.003), indicating a declining trend in TT levels with escalating miscarriage occurrences. Conclusion: In patients undergoing IVF-ET, advanced maternal age, lower TT levels, increased WHR, and elevated FINS levels emerged as potent risk factors for RPL. These findings provide clinicians with valuable insights and facilitate the identification of patients who are at high risks and the formulation of preventive strategies to reduce the recurrence of miscarriages.

Development and validation of KASP markers for resistance to Phytophthora capsici in Capsicum annuum L.

Resistance of Capsicum annuum to Phytophthora blight is dependent on the genetic background of the resistance source and the Phytophthora capsici isolate, which poses challenges for development of generally applicable molecular markers for marker-assisted selection. In this study, the resistance to P. capsici of C. annuum was genetically mapped to chromosome 5 within a 1.68-Mb interval by genome-wide association study analysis of 237 accessions. In this candidate region, 30 KASP markers were developed using genome resequencing data for a P. capsici-resistant line (0601 M) and a susceptible line (77,013). Seven of these KASP markers, located in the coding region of a probable leucine-rich repeats receptor-like serine/threonine-protein kinase gene (Capana05g000704), were validated in the 237 accessions, which showed an average accuracy of 82.7%. The genotyping of the seven KASP markers strongly corresponded with the phenotype of 42 individual plants in a pedigree family (PC83-163) developed from the P. capsici-resistant line CM334. This research provides a set of efficient and high-throughput KASP markers for marker-assisted selection of resistance to P. capsici in C. annuum. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-023-01367-3.

Fine mapping of Rf2, a minor Restorer-of-fertility (Rf) gene for cytoplasmic male sterility in chili pepper G164 (Capsicum annuum L.).

KEY MESSAGE: Genome re-sequencing and recombination analyses identified Capana06g000193 as a strong candidate for the minor male fertility restoration locus Rf2 in chili pepper G164 harboring two dominant male fertility restoration genes. Male fertility restoration genes of chili pepper restorer line G164 (Capsicum annuum L.) were studied using molecular marker genotypes of an F2 population (7G) of G164 crossed with the cytoplasmic male sterility line 77013A. The ratio of sterile to fertile single plants in the F2 population was 1:15. This result indicates that chili pepper G164 has two dominant restoration genes, which we designated as Rf1 and Rf2. An individual plant recessive for Rf1 and heterozygous for Rf2, 7G-112 (rf1rf1Rf2rf2), was identified by molecular marker selection and genetic analysis, and a single Rf2 gene-segregating population with a 3:1 ratio of fertile to sterile plants was developed from the self-pollination of male fertile individuals of 77013A and 7G-112 hybrid progeny. Bulk segregant analysis of fertile and sterile pools from the segregating populations was used to genetically map Rf2 to a 3.1-Mb region on chromosome 6. Rf2 was further narrowed to a 179.3-kb interval through recombination analysis of molecular markers and obtained the most likely candidate gene, Capana06g000193.

Immunity and coagulation and fibrinolytic processes may reduce the risk of severe illness in pregnant women with coronavirus disease 2019.

BACKGROUND: There are specific physiological features regarding the immunity and coagulation among pregnant women, which may play important roles in the development of coronavirus disease 2019. OBJECTIVE: This study aimed to determine the key factors associated with the deterioration of patients with coronavirus disease 2019 and the differentiating clinical characteristics of pregnant women with coronavirus disease 2019 to interfere with the progression of coronavirus disease 2019. STUDY DESIGN: A retrospective study of 539 Chinese Han adult patients with coronavirus disease 2019 was conducted, of which 36 cases were pregnant women. In addition, 36 pregnant women without coronavirus disease 2019 were recruited as the control. The characteristics of severe and critical illnesses, which were differentiated from mild and moderate illnesses in patients with coronavirus disease 2019, were analyzed using a machine learning algorithm. In addition, major differences between pregnant women with coronavirus disease 2019 and age-matched nonpregnant women with severe or critical coronavirus disease 2019, paired with pregnant women without coronavirus disease 2019, were explored to identify specific physiological features of pregnant women with coronavirus disease 2019. RESULTS: For the total patient population, the lymphocyte, CD3+, CD4+, CD8+, CD19+, and CD16+CD56+ cell counts were significantly lower, and white blood cell count, neutrophil count, and neutrophil-to-lymphocyte ratio were higher in those with severe or critical illness than those with mild or moderate illness (P<.001). The plasma levels of interleukin-6, interleukin-10, and interleukin-6-to-interleukin-10 ratio were significantly increased in patients with critical illness compared with patients with mild, moderate, and severe illnesses (P<.001). The above immunologic coclusters achieved an area under the receiver operating characteristic curve of 0.801 (95% confidence interval, 0.764-0.838), and its combined model with the coagulation and fibrinolysis indices (prothrombin time, D-dimer) achieved an area under the receiver operating characteristic curve of 0.815 (95% confidence interval, 0.779-0.851) using the random forest regression model to predict severe or critical illness. For pregnant women with coronavirus disease 2019, none had preexisting diseases. Compared with nonpregnant women with mild or moderate coronavirus disease 2019, pregnant women with coronavirus disease 2019 displayed increased white blood cell count, neutrophil count, neutrophil-to-lymphocyte ratio, and levels of D-dimer and fibrinogen, along with decreased lymphocyte and interleukin-4 levels (P<.05). Although they presented similar changes of immunologic markers of lymphocyte; white blood cell count; neutrophil-to-lymphocyte ratio; CD3+, CD4+, CD8+, and CD16+CD56+ cell counts; and interleukin-6-to-interleukin-10 ratio, compared with nonpregnant women with severe or critical coronavirus disease 2019, none of the pregnant women with coronavirus disease 2019 deteriorated into severe or critical illness. There was no significant difference in white blood cell count, lymphocyte count, neutrophil count, neutrophil-to-lymphocyte ratio, immunologic markers, or coagulation and fibrinolysis markers between pregnant women with coronavirus disease 2019 and pregnant women without coronavirus disease 2019. As for the discrepancy of pathophysiological features between pregnant women with coronavirus disease 2019 and nonpregnant women with severe or critical coronavirus disease 2019, the immunologic markers achieved an area under the receiver operating characteristic curve of 0.875 (95% confidence interval, 0.773-0.977), and its combined model with coagulation and fibrinolysis indices achieved an area under the receiver operating characteristic curve of 0.931 (95% confidence interval, 0.850-1.000). CONCLUSION: Immune dysregulation was identified as a crucial feature of patients with coronavirus disease 2019, which developed severe or critical illness, and pregnant women with coronavirus disease 2019 presented with similar immune responses but rarer incidences of severe or critical illness. Immune dysregulation is related to the risks of deterioration into severe or critical illness. The specific coagulation and fibrinolysis systems of pregnancy may reduce the risk of pregnant women with coronavirus disease 2019 without preexisting disease from developing severe illness.

Development and application of KASP markers associated with Restorer-of-fertility gene in Capsicum annuum L.

Fertility restoration of cytoplasmic male sterility (CMS) in Capsicum annuum is controlled by multiple alleles of Restorer-of-fertility (Rf) genes. The isolation of additional Rf genes should therefore enrich the knowledge of CMS/Rf systems and accelerate their exploitation in hybrid seed production. In this study, the fertility restorer gene CaRfm of '0601 M', a non-pungent bell pepper, was genetically mapped to a 1.2-cM region flanked by KASP markers S761 and S183. CaRfm was then physically mapped to a 128.96-Kb interval predicted from 24 recombinants with two co-segregated markers, S423 and S424. CaPPR6 encoding a pentatricopeptide repeat (PPR) protein was suggested as the most likely candidate gene for the CaRfm locus on the basis of sequence alignment as well as genotyping of tightly linked markers. In addition, molecular markers S1597 and S1609, which are immediately adjacent to CaRfm at 15.7 and 57.8-Kb respectively, were developed and applied to marker-assisted selection. The results provided friendly markers for breeding pepper restorer lines and laid the foundation for elucidating the male fertility restoration mechanism. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s12298-021-01109-9.

Fine mapping of the major anthracnose resistance QTL AnRGO5 in Capsicum chinense 'PBC932'.

BACKGROUND: Colletotrichum species are the causal agents of anthracnose, a major disease affecting the yield and quality of pepper (Capsicum spp.). Colletotrichum scovillei is widespread in China, has strong pathogenicity and drug resistance, and causes anthracnose disease in pepper fruits that severely reduces production. Previously, an anti-anthracnose locus AnRGO5 was mapped to the P5 chromosome on the basis of analyses of fruit at the green mature stage. The aim of this study was to narrow down the interval of this locus and identify the gene responsible for conferring resistance. RESULTS: On the basis of results of re-sequencing of Capsicum chinense 'PBC932' and C. annuum '77013', we developed Kompetitive allele-specific PCR (KASPar) markers and insertion-deletion (InDel) markers linked to AnRGO5 at the green mature fruit stage and used them to construct a genetic linkage map (42 markers, 24.4 cM in length). Using data obtained in phenotypic and genotypic analyses of BC4S1, BC4S2, and BC4S3 populations, AnRGO5 was located between the markers P5in-2266-404 and P5in-2268-978 within a physical distance of 164 kb. This region contained five genes, including CA05g17730. CA05g17730 encodes 'R1C-3-like' putative late blight resistance protein homologs. The transcript level of CA05g17730 differed between 'PBC932' and '77013'. The structure of the CA05g17730 gene also differed between 'PBC932' and '77013'. CONCLUSIONS: We narrowed down the QTL interval to a region containing five genes. These results will be useful for further research on the mechanisms of resistance to anthracnose, and for marker assisted selection for anthracnose-resistant capsicum lines.

Fine mapping of the male fertility restoration gene CaRf032 in Capsicum annuum L.

KEY MESSAGE: A novel strong candidate gene CA00g82510 for the male fertility restoration locus CaRf032 in Capsicum annuum was identified by genome re-sequencing and recombination analysis. A single dominant locus (CaRf032) for fertility restoration of cytoplasmic male sterility was identified in the strong restorer inbred line IVF2014032 of chili pepper (Capsicum annuum L.). CaRf032 was localized within an 8.81-Mb candidate intervals on chromosome 6 using bulked segregant analysis based on high-throughput sequencing data. Subsequently, the candidate interval was genetically mapped and defined to a 249.41-kb region using an F2 population of 441 individuals generated by crossing the male-sterile line 77013A and the restorer line IVF2014032. To fine map CaRf032, eight newly developed KASP markers were used to genotype 23 recombinants screened from a larger F2 population of 2877 individuals. The CaRf032 locus was localized to a 148.05-kb region between the KASP markers S1402 and S1354, which was predicted to contain 22 open reading frames (ORFs). One ORF with an incomplete sequence was predicted to contain a PPR motif, and its physical position overlapped with the Rf candidate gene CaPPR6_46. The PPR ORF sequence before the gap showed 100% identity with the CA00g82510 locus of the CM334 reference genome. CA00g82510 encodes a protein of 583 amino acids, containing 14 PPR motifs, and shows significantly differential expression between the flower buds of the maintainer line 77013 and the restorer line IVF2014032. These results indicated that CA00g82510 is a strong candidate gene for CaRf032. Five KASP markers, which detected single-nucleotide polymorphisms in CA00g82510 of 77013 and IVF2014032, co-segregated with CaRf032 and showed 64.4% successful genotyping of 38 maintainer and 63 restorer lines.

Pepper variome reveals the history and key loci associated with fruit domestication and diversification.

Pepper (Capsicum spp.) is an important vegetable crop that provides a unique pungent sensation when eaten. Through construction of a pepper variome map, we examined the main groups that emerged during domestication and breeding of C. annuum, their relationships and temporal succession, and the molecular events underlying the main transitions. The results showed that the initial differentiation in fruit shape and pungency, increase in fruit weight, and transition from erect to pendent fruits, as well as the recent appearance of large, blocky, sweet fruits (bell peppers), were accompanied by strong selection/fixation of key alleles and introgressions in two large genomic regions. Furthermore, we identified Up, which encodes a BIG GRAIN protein involved in auxin transport, as a key domestication gene that controls erect vs pendent fruit orientation. The up mutation gained increased expression especially in the fruit pedicel through a 579-bp sequence deletion in its 5' upstream region, resulting in the phenotype of pendent fruit. The function of Up was confirmed by virus-induced gene silencing. Taken together, these findings constitute a cornerstone for understanding the domestication and differentiation of a key horticultural crop.