Comparison of whole genome amplification and nested-PCR methods for preimplantation genetic diagnosis for BRCA1 gene mutation on unfertilized oocytes-a pilot study

Detecting the Frequency of c.5946delT Pathogenic Variant in the BRCA2 Gene and Associated Risk Factors Among Breast Cancer Patients Visiting Felege Hiwot Referral Hospital and University of Gondar Comprehensive Specialized Hospital

Background

Breast cancer is one of the most common cancers and the leading cause of death for women worldwide, and the problem is currently getting worse. In Ethiopia, it has become one of the most prevalent cancers, with high rates of morbidity and mortality. The BRCA2 gene variant c.5946delT has been linked to a higher risk of developing breast cancer.

Objective

The aim of the present study was to detect the presence of the c.5946delT pathogenic variant in the BRCA2 gene and associated risk factors among breast cancer patients visiting FHRH and UoGCSH.

Methods

A cross-sectional study was conducted from September 2021 to October 2022. Peripheral blood samples were collected from 100 patients with breast cancer, and gDNA was extracted using the salting-out method as per the protocol provided in the manufacturer's instructions. The BRCA2 gene c.5946delT variant was detected using the PCR-RFLP technique. The data were analyzed using SPSS version 23. P≤ 0.05 was considered statistically significant.

Results

In this study, we discovered that 2% of breast cancer patients had a c.5946delT pathogenic variant of the BRCA2 gene. In addition, the results suggested that the c.5946delT pathogenic variant and age at diagnosis were significantly correlated. On the other hand, there was no significant association between inhabitance and family history for the c.5946delT variant.

Conclusion

We have found out that breast cancer patients in the study area had the BRCA2 gene variant c.5946delT, which suggests that this pathogenic variant is linked to breast cancer. Hence, assessing gene alterations using the PCR technique is one of the most effective early diagnostic strategies for breast cancer that should be used in hospitals in order to lower mortality.

Preimplantation Genetic Testing for Breast Cancer

Breast cancer (BC), a malignant tumor characterized mainly by a lump in the breast and a change in breast shape, has plagued many women of childbearing age in Nigeria today. This has thus propelled many to find both prophylactic and curative agents to combat BC in affected persons. This article extensively reviews a method of preventing BC in the offspring of affected parents, known as preimplantation genetic testing (PGT) – an assisted reproductive technique that selects genetically unaffected embryo(s) to be transferred to the uterus of a mother upon in vitro fertilization and standard genetic analysis. The present study also seeks to present the techniques involved in PGT that have been reported to prevent the inheritance of BC, its benefits and risks, related case studies in Africa and other continents, and ethical issues surrounding the application of assisted reproduction for BC testing. To achieve these, a thorough search was conducted in reputable scientific journals of reproduction and cancer, and expert knowledge was consulted with regard to these aspects of health and reproduction. Upon reviewing this very important subject, it was confirmed that the beneficial role of assisted reproduction in the field of science and the homes of many cannot be overestimated. This review of the role of PGT in BC prevention will enlighten the understanding of many – creating awareness that with PGT, BC-affected women can have not only children, but also healthy and genetically unaffected children.

Healthy Baby Born to a Robertsonian Translocation Carrier following Next-Generation Sequencing-Based Preimplantation Genetic Diagnosis: A Case Report

Preimplantation genetic diagnosis (PGD) is well established method for treatment of genetic problems associated with infertility. Moreover, PGD with next-generation sequencing (NGS) provide new possibilities for diagnosis and new parameters for evaluation in, for example, aneuploidy screening. The aim of the study was to report the successful pregnancy outcome following PGD with NGS as the method for 24 chromosome aneuploidy screening in the case of Robertsonian translocation. Day 3 embryos screening for chromosomal aneuploidy was performed in two consecutive in vitro fertilization (IVF) cycles, first with fluorescent in situ hybridization (FISH), and then with NGS-based protocol. In each IVF attempt, three embryos were biopsied. Short duration of procedures enabled fresh embryo transfer without the need for vitrification. First IVF cycle with the embryo selected using PGD analysis with the FISH method ended with pregnancy loss in week 8. The second attempt with NGS-based aneuploidy screening led to exclusion of the following two embryos: one embryo with 22 monosomy and one with multiple aneuploidies. The transfer of the only euploid blastocyst resulted in the successful pregnancy outcome. The identification of the euploid embryo based on the NGS application was the first successful clinical application of NGS-based PGD in the case of the Robertsonian translocation carrier couple.

Successful nonsurgical transfer of bovine elongating conceptuses and its application to sexing

The objectives of the present study were to establish a nonsurgical transfer method for elongating bovine conceptuses and to combine this method with biopsy and sexing. Bovine conceptuses were recovered from donor cows on days 13-14 of the estrus cycle. In experiment 1, day 13 conceptuses were transferred to recipient cows using a standard day 7 embryo transfer (ET) method. The pregnancy rate of day 13 conceptus transfer (CT) is comparable to that of day 7 ET. In experiment 2, day 14 conceptuses were transferred using modified methods (balloon catheters or ET guns with modified sheaths). Using the standard ET method, no pregnancies were obtained; however, when balloon catheters or ET guns with modified sheaths were used, the pregnancy rates after CT were 48.0% and 44.8%, respectively. In experiment 3, day 14 conceptuses were biopsied without a micromanipulator, sexed using the loop-mediated isothermal amplification method and transferred to recipient cows. The pregnancy rate of biopsied conceptuses was 46.2% and did not differ significantly from that of unbiopsied conceptuses. Moreover, all pregnant cows transferred conceptuses following biopsy and sexing delivered calves with the expected sexes. These results suggested that the nonsurgical bovine CT method was comparable to day 7 ET and that this technique enables biopsy and sexing without expensive equipment such as a micromanipulator or specialized skills.