Molecular Biology Techniques Applied to Assisted Reproduction

Contents

1. Introduction
1.1 Background to the study
1.2 Statement of the problem

2. Literature Review
2.1 Male Infertility
2.1.1 Whole chromosomal aberrations
2.1.2 Partial chromosomal aberrations
2.1.3 Single gene mutations
2.2 Female genetic infertility
2.2.1 Chromosomal aberrations
2.2.2 Fragile X syndrome
2.3 Molecular Biology Techniques in Assisted Reproduction
2.3.1 In-vitro fertilization and embryo transfer (IVF)
2.3.2 Intracytoplasmic sperm injection (ICSI)

3. Discussion
3.1 Molecular techniques for detecting genetic illnesses that are transmissible to offspring
3.2 Single gene disorders

4. Advancement in Molecular Biology in Assisted Reproduction

5. Ethical Considerations

6. Conclusion

References

1. Introduction

1.1 Background to the study

According to the World Health Organization, infertility affects may couples worldwide with millions having to live with infertility issues. It is estimated that nearly 186 million people, and 48 million couples worldwide contend with the issue of infertility (WHO, 2021). It therefore presents a worrying trend for many people who wish to have children of their own. Infertility affects both women and men, with the population witnessing different prevalence’s in the two genders. For instance, in North American 4.5 – 6 percent of men are affected by male infertility, while about 12% of women aged between 15-44 years will experience fertility issues. This shows therefore that there are differences in how fertility affects both males and females.

Infertility can cause serious mental torture, with the individual who is unable to get a child met with suspicion and stigma. This is actually true in developing countries, where the issue of infertility is closely associated with traditional beliefs, and stigmatization is directed on the side of the woman in the relationship. The medical advancement in developing countries is also lagging behind which makes it challenging and expensive for couples to get treatment for infertility. It makes it virtually impossible for the vulnerable in the society to get an effective solution to their problem when the health resources in the country are almost non-existent.

Since the infertility issues affects a significant portion of the population, the medical world has sought lasting solutions that could help couples who are unable to conceive to get a chance to get pregnant, and get their own children. The quest to find a solution for couples affected by infertility issues necessitated molecular biologists to find techniques that could be used to help them conceive and get pregnant. There has been advancement in the field, with history dating as back as 1978 when the first child to be sired using assisted reproductive means was born. Since then, there has been an explosion of and rapid advancement in the field of assisted reproduction, which has helped many people achieve the dream of having children.

In recent decades, there have been a number of significant advances in reproductive and microbiology that have effectively made these two fields inexorably intertwined. Today, molecular biology is vital in all stages of development, from diagnostic procedures to the selection of the most cutting-edge drugs. Genetic screening, in particular, is utilized in assisted reproduction for three key purposes: diagnosing the causes of infertility, discovering genetic disorders that may be passed down to children, and perfecting assisted reproductive technology (ART) The total fertility rate is dropping; for example, in the United States, 13% of women get fertility treatment at some time in their life. As a consequence, it is vital to support reproductive journeys of couples. To have a child, both spouses' reproductive systems must be integrated and properly coordinated; consequently, evaluating both people in the relationship is critical. A medical evaluation is essential when a couple is unable to conceive one year after indulging in unprotected intercourse. Currently, the clinical chronology of infertile couples comprises molecular and operational studies that allow for a diagnosis in 65 percent of cases; hereditary testing is undertaken in the other 35 percent of instances that go unnoticed. Recognizing that approximately 15% of genetic illnesses are associated with reproductive disorders and that relevant medical symptoms can be caused by both non-genetic and genetic causes, it is critical that a fertility problems diagnosis be made using a combination of the clients' specific medical records and instrument- and laboratory-based evaluations, including targeted genetic screening. Genetic screening (testing and counseling) to confirm a particular diagnosis may aid in the provision of more precise and focused healthcare.

The aim of this paper will be an attempt to review available molecular biology techniques that can be used to offer effective treatment solution for couples who are unable to get pregnant. Due to a wide range of options available, it is important to find evidence-based techniques that are proven to offer positive results.

1.2 Statement of the problem

Many couples and people around the world experience fertility issues, which affects their ability to conceive children. A majority of the affected people do not know where to get appropriate treatment, which further worsens their mental burden. There are available treatment solutions available to them, but many are not backed by research or science and can prove to be dangerous. This therefore necessitates the need to find appropriate molecular biology techniques applied to assisted reproduction, which can be helpful to affected couples and individuals.

2. Literature Review

In this literature review will be an analysis of studies covering on the topic of molecular biology techniques in assisted reproduction. The first part of this chapter will be an explanation of the causes of male and female infertility. This will be followed by a description of molecular biology methods that are used to assist couples who have been unable to conceive to get pregnant.

2.1 Male Infertility

Cells that are going to become germ are supposed to normally take on different destiny from other cells that are in the embryo as early as possible and particularly throughout embryogenesis. Germ cells are meant to sustain species by transmission of genetic elements to next generation. The male germ cells go through meiosis and morphogenesis in an extensive manner so that they can alter the cells which are round shaped to sperm cells that can travel in a free manner driven by flagellum and moving to seek the missing half. The additional genes and regulatory systems are needed so that the unique traits are got. If a significant number of male fertility genes are necessary in mammals, disruptive mutations in those genes are related with an elevated risk of male fertility disorders.

Chromosomal anomaly is an abnormality is in men where some males have severe male factor infertility and is detected by checking the blood chromosomes (Karyotype)so that they can have an extra x chromosome. This indicates that instead of the males having 46XY karyotype, what they have is 47XXY karyotype. This kind of illness is known as Klinefelter Syndrome and will bring about inability to achieve puberty and even if it is achieved the guy would be infertile. Men with Klinefelter Syndrome can make someone pregnant by use of in vitro fertilization (IVF) and this is done by use of Intra-Cytoplasmic Sperm Injection (ICSM) (ICSM)

The Y chromosome micro-deletions are where certain males have poor sperm count and this is because they have deletions in specific areas of their Y chromosome and this is known as DAZ gene. The karyotype of the males is normal with 46XY; nevertheless, a thorough study of Y chromosome will indicate that some of the pieces are missing. A portion of these male will have no sperm in testicular surgery and hence the only option is donation cells (Silber et al 1994). When there are other deletions in DAZ gene there is a little number of sperm that is present and hence conception can be obtained with IVF-ICFSI. The male offspring that has acquired the father’s genes will eventually be infertile too for they will carry the Y chromosome.

Most of the causative divisions of male fertility have been tied to hereditary inheritance. Over than 200 hereditary disorders have been related to sexual dysfunction, varying from the most frequent clinical presentations of infertility to the strangest complicated abnormalities with clinical symptoms that stretch across fertility issues, as per our study. According to Begum (2008) infertility is generally only one of numerous clinical indications of a severe condition; nonetheless, in certain inherited diseases, infertility is the most prominent phenotypic trait. Additionally, it is important to follow these infertile individuals over time since they have been proved to have a larger morbidity rate and a low life expectancy than the overall population. In scenarios of severe oligospermia, the development of variations in the spermiogram is now the major indicator for genetic testing, especially in hormonal levels, anomalies, frequent abortions, and genetic predisposition. Recent research revealed that the percentage of genes indisputably linked to the more prevalent phenotypes of oligozoospermia or azoospermia remain restricted (50 percent); the other half are genes linked in teratozoospermia, despite the monomorphic forms of teratozoospermia being highly rare. Entire chromosomal abnormalities (structural or numerical), incomplete chromosomal aberrations (microdeletions of the Y chromosome), and monogenic diseases are all genetic disorders associated to male infertility. Sex chromosomal deficits have a larger influence on spermatogenesis, whereas genetic mutations are more connected to hypogonadism, teratospermia, or asthenozoospermia, as well as familial variants of obstructive azoospermia.

2.1.1 Whole chromosomal aberrations

First most similar genetic indicators used to detect infertility in men and are the karyotype, the evaluation of chromosomes Y chromosomal abnormalities, and the analysis of the CFTR gene. Because several abnormalities have been linked to male infertility, it is not unusual for the biologically predetermined cause of 40% of all male infertility to remain unanswered. It's also important to note that the role of de novo mutations should be extensively investigated, especially in the light of what occurs with Klinefelter syndrome and AZF deletions, which occur almost entirely. As a result, in order to optimize and customize the whole testing and therapy route of male infertility, targeted genetic variants should be conducted in the detection of specific clinical illustrations, every after suitable genetic counselling and primarily for clinical diagnosis, during clinical decision-making to classify the most effective ART approach (for instance, mostly in existence of deletions of the AZFa and AZFb zones, the possibility of sperm restoration should be considered) (for example, in the presence of deletions of the AZFa and AZFb regions, the possibility of sperm recovery using testicula). If it comes to general genetic abnormalities, the incidence of genetic variations varies in newborns (Begum,2008). When it comes to numerical abnormalities, structural chromosome inversions are more common; nevertheless, this will not apply to y chromosome, whose aberrations, chromosomal aberrations, are characterized by aneuploidies and structural chromosomal rearrangements of chromosome Y.

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