Genetics and Prenatal Development - Research Paper Example

? Genetics and Prenatal Development The report purposes to examine research into genetics and prenatal development of the fetus effect on growth and development rate and the physical attributes of the infancy stage of human beings and provide a summary. The arguments in the report focus on the pregnancy period and the relationships of the genetics and prenatal development. Research into the paper dealt with the outsourcing of information from relevant books and comparing the information. The results strengthen the arguments that the two factors determine the development of humans in the infancy stage of life. The report first addresses genetic relationships and their affect prenatal and infancy development. It gives the effect of different relationships on the development of the fetus and the various environmental factors that affect the relationships and interactions of the genes. The report next reviews prenatal development and the factors that predetermine the outcome and offers recommendations on the maintenance of a healthy development process. The common pregnancy problems that may have drastic results are also examined. Finally, a conclusion offers recommendations on ways of finding out the effect of genes and ensuring a healthy prenatal development as ways of avoiding pregnancy complications and enhancing infancy development. Keywords: genotype, phenotype, chromosomes, environment Introduction Infancy is the period of being a minor especially before one acquires the ability to walk. In humans, the term infant refers to the very young offspring. The growth and development of an infant rely on a number of factors that may act as building blocks for the child (Kail and Cavanaugh, 2013). However genetics and prenatal development are the Factors in the period before birth that influence the rate of growth and development of an infant. Genetics deals with the processes of trait inherited by the offspring from the parent. This incorporates molecular function and structure of genes, their behavior, distribution and variation and the resulting changes in their populations. Prenatal development also called antenatal development is the process that takes place after fertilization of the human ovum that sees the human embryo gestate during a pregnancy in preparation for birth. Embryogenesis ends during the 10th week of gestation with the completion of the development of all precursors of the major body organs. The genetic characteristic of the fetus and the antenatal development determine the rate and nature of the growth and development of the infant. Genetics Fertilization, the process through which an ovum and a sperm join and form a zygote is the start of life. The fusing of these cells brings together the chromosomes contained in each cell. These act as the human life blue print and contain the DNA, a chemical structure containing the genetic code for the formation of the human cells (Sigelman and Rider, 2011). Each of the reproductive cells contains 23 chromosomes that add up to 46, the chromosome number in all other cells of the human body. This facilitates the inheritance of the parents’ characteristics of the offspring. The genes inherited by the offspring are the genotype of the offspring. The express traits derived in the form of height and other physical characteristics make up the phenotype of the person. The genes inherited by the offspring will determine the characteristics of the offspring. This will decide the growth rates and nature exhibited by the offspring. However, the expression of the genes depends on the coming together of the genes in terms of the interaction of the gene with other genes and the environment. Genetic interactions Different genes are likely to contain conflicting genetic information. In such cases the genes compete for dominance. The stronger gene suppresses the other gene to result in phenotypes of the former being exhibited (Newman and Newman, 2012). However, the interaction may be exhibited in an additive way. The height genes are an example of this kind of interaction. If an offspring has one short parent and one tall parent, the phenotype of the offspring exhibited in terms of height may be an average of the two with the child having average height. In some cases, the gene interaction is predefined by the recessive-dormant pattern associated with the genes (Newman and Newman, 2012). This is illustrated in the eye color gene. If one parent has brown eyes and the other blue eyes, the offspring is more likely to have brown eyes. This is due to the fact that the brown eyes gene is dominant over the blue eyes gene that is recessive. Gene-environment interactions The genes act as the blueprint of human life. This means they determine the characteristic of the child. However, the environment also plays an important role in determining the characteristics and development of the infant. This applies for both prenatal and after birth environmental conditions (Bjorklund, 2012). This determines how and which genes are expressed. The conditions exposed to the child in utero dramatically affect the child’s development. Conducive conditions with proper nutrition favor the development of the child with the instructions of the genes expressed fully. However, exposure to harmful conditions in the form of harmful drugs and inadequate nutrition in utero has the opposite effect. For example, the height of the child may be repressed because of this. The genetic coding of the child may have the instructions necessary for tallness. The conditions in uterus may draw up a suppression of these genes and result in the child exhibiting a phenotype that is the opposite of the instructions. Smoking among pregnant mothers is linked to reduced newborn weights. This results in weakening of the immune system of the child, as well as neurological and respiration impairment (Greer and Nelson-Piercy, 2007). Alcohol abuse in the months of pregnancy leads to a serious alcohol syndrome linked to body malformations, mental retardation, and heart defects. Psychoactive drugs like cocaine and methamphetamine also cause neurological impairment and reduced birth weights. The human genes are also suppressed by diseases occurring during the pregnancy period (Greer and Nelson-Piercy, 2007). These include rubella, herpes, and AIDS. The situation is worse for herpes virus as it is transmittable to the fetus and results in modification of the genes causing deafness, mental retardation, and brain swelling. However, delivery through cesarean section reduces the threat of transmission. Genetic abnormalities Genetic abnormalities are instances where the genetic coding of the cells of an organism is not in line with the normal genetic makeup of the species. The genetic makeup of each species is not a foolproof chemical structure and is subject to wrongs (Kail and Cavanaugh, 2013). During the process of fertilization when the sperm and the ovum meet, an uneven distribution of then chromosomes may arise resulting in the cells having more or less of the normal 23 chromosome number of the human cell. These cells join with normal cells yielding zygotes with uneven chromosomes. These zygotes develop into a fetus and finally babies born with syndromes that distinguish them from normal babies as they create a set of abnormal characteristics. Abnormalities of the sex chromosomes The chromosomes determine the sex of the fetus. The ovum carries an X chromosome. The sperm fusing with the ovum carries the other chromosome that determines. If the sperm gives another X chromosome, the sex is female. Y-chromosomes result in a male sex. Nevertheless, there are distinct instances. In every 500 births, one child is born missing or having an excess X chromosome (Sigelman and Rider, 2011). This results in abnormalities materializing in the form of Fragile X, Turner, and Klinefelter syndromes. Klinefelter’s Syndrome results from the inclusion of an extra X chromosome. The syndrome causes repression in the development of secondary sex characteristics and disabilities in learning. Fragile X results from the attachment of part of an X chromosome to other chromosomes through a thin string of molecules. This poses a danger of the partly attached chromosome breaking off from the others. Though it affects both genders, its impacts vary. The syndrome may show little signs or develop as a mild or severe case of mental retardation. Turner’s syndrome, which occurs only in females, occurs if there is only one sex chromosome present (Newman and Newman, 2012). The subject exhibits characteristics of a webbed neck, short stature and a deficiency of the secondary sex characteristics. Difficulties in recognizing emotions portrayed in facial expressions and learning disabilities are some psychological defects associated with the syndrome. Inheritance of diseases and defects A number of diseases are known not to be contagious and are instead inherited from the parents of an offspring. These include Sickle-cell anemia, Tay-Sachs disease, Cystic fibrosis, and to a little extent diabetes. This hereditary nature of the diseases is a result of the genetic coding of the genes of humans (Greer et al, 2007). If a parent is a carrier of one of these diseases, he or she may transfer it to the offspring through the genes. However, this phenomenon does not mean that all of the offspring of a hereditary carrying human will inherit the disease. Genetic tests can be done to determine whether one is a carrier of genes for a certain disease in order to prepare for the offspring. Certain defects of the human body, such as Albinism, are also determined by the genetic makeup of the cells. Carriers of the gene may not exhibit its characteristics, but the offspring of the carrier may display them (Newman and Newman, 2012). The genetic makeup of the parent therefore determines the development of the offspring as it determines the defects inherited by the offspring. Tests can also show the defect genes in a carrier. Prenatal development and prenatal care Prenatal development Prenatal development is the process of the growth and development of a baby in utero from a single cell after fertilization to a zygote, embryo, and finally a fetus before giving birth (Wehby, 2006). This process averages a time period of around 38 weeks and commences at the cellular level through the fusion of the male and female gametes. The fusion forms the zygote which consists of the base prototype of the genetic material from which the cells of the fetus develop. Prenatal development consists of three stages namely germinal, embryonic, and fetal stages. The germinal stage starts immediately after fertilization and fusion of the reproductive cells. The zygote formed starts dividing rapidly day mitosis in a process known as cleavage. One cell divides into two other cells with the same number of chromosomes. These dividing cells travel down the Fallopian tube and enter the uterus after three days. Here a fluid cavity form at the center of then cells and forms a basis for the implantation on the uterine wall 3 days later. The implantation is the end of the stage and the start of the embryonic stage (Greer et al, 2007). This stage lasts until the eight weeks of the pregnancy. Differentiation starts with rapid division creating clusters of cells that take up specific functions. Different structures are formed simultaneously as a result. At the end of the stage, all vital structures that are both internal and external are complete. The embryo is now called the fetus. This stage sees the development of the structures formed in the embryonic stage so that the fetus is ready for birth with all its parts functioning. The nature of these processes is a great determiner of the development of the infant after birth. The growth regulation is a highly complex activity dependent on the interaction of hormones, genetics, nutrition, and environmental factors. The nutrition of the mother is important as the fetus requires energy and nutrients to grow and therefore feeds off the food in the mother’s bloodstream (Bjorklund, 2012). A diet void of the essential vitamins and minerals like vitamin C and calcium will hinder the fetal development. These nutrients are needed for bone formation and their deficiency results in weak bone structures that will hinder development postnatal. Bad nutrition will also hinder the general development of the fetus resulting in a low birth weight that causes respiratory limitations that hinder development. The environment that the mother is exposed to is a determiner of the outcome of the fetus. Exposure to agents such as heavy metals like lead, radiation, or chemical teratogens results in abnormalities of the chromosomes in terms of translocation, deletion, and mutation. Depending on the stage of exposure, this changes the body structures and results in underdeveloped features and complete absence of limbs in extreme cases. These are likely to weigh down the rate of growth and development in the infant (Greer et al, 2007). Toxoplasmosis, an infection in pregnant women that results from the consumption of uncooked eggs and meat as well as unpasteurized milk, negates mental development of the newborn by causing cerebral palsy, microcephaly, and hydrocephalus. The hormones of the mother such as osteocalcin, determine the development of the child. A deficiency of the hormones hinders the development of the fetus, which results in an underdeveloped and underweight baby with respiratory complications that slow down growth, and development (Kail and Cavanaugh, 2013). The hormones can also cause a premature birth with an underdeveloped baby with immunity and respiratory issues that negate the development. In some instances, there exist abnormalities in the fetus in the process of prenatal development resulting in malformations and delays in development. These are natural occurrences resulting from mutations, damaged genes, chromosome abnormalities, errors in prenatal development or inheritance of the defect. These abnormalities may be minor with no effect or major ones that influence the long term prognosis of the child after birth (Sigelman and Rider, 2013). Prenatal care Also called antenatal care, prenatal care is the regular medical checkup and care recommended for pregnant women during the pregnancy period (Wehby, 2006). This is a form of preventive health care seeking to provide regular checkups enabling doctors to monitor pregnancies in order to treat and prevent health situations that may pose risks to the well being of the mother and child. The checkups offer advice on the changes experienced by the mother and child and recommend healthy lifestyle changes. Defects and deformities are detected and the proper treatments administered to counter them. Prenatal care is important in a healthy gestation period with a healthy birth with minimized complications (Wehby, 2006). This helps the chances of a healthy infant and in turn improves the growth and development of the infant. Pregnancy problems Complications of pregnancy are the health problems resulting from pregnancies. Pregnancies are associated with certain symptoms and discomforts. However, some of them turn out to be severe and interfere significantly with day-to-day activities. Normal symptoms and discomforts do not pose threats to the well being of mother and child (Greer et al, 2007). If they pose a threat, they are labeled complications of pregnancy. The complications are many but there are seven of them that are very common. Severe bleeding during a pregnancy can be an indicator of ectopic pregnancy or miscarriage. Many women experience spells of nausea and vomiting when pregnant. However, a severe occurrence causes water electrolyte imbalance that endangers the life of the fetus (Greer et al, 2007). Movements of the baby are normal after a drink or a meal. A significant decline in the activity of the baby means a reduction in its energy, which could be an implication of a problem. Early contractions in the third trimester indicate a hormonal change, which requires immediate medical attention (Greer et al, 2007). Persistent severe visual disturbances, swelling, abdominal pain, and headaches in the third trimester are a sign of the potentially fatal preeclampsia marked by high blood pressure. This is harmful to both mother and child and requires immediate diagnostics and treatment. Flu during a pregnancy is likely to result in major complications that may be fatal. This is avoidable by administration of the flu vaccine. Conclusion Genetics and prenatal development are important points of focus during a pregnancy. The genetics will determine the characteristics of the infant and help determine the potential conditions of the fetus. The genetics also determine the characteristics of the baby in uterus and after birth. This means they determine the growth and development of the infant. The process of prenatal development is a complex process that determines the nature and characteristics of the infant. The process nature relies on a number of factors that determine its nature. It is important to attend prenatal care checkups to get advice and recommendations during pregnancies. This will go a long way in avoiding pregnancy complications that may turn out to be fatal. References Bjorklund, D. F. (2012). Child & adolescent development: An integrated approach. Belmont: Wadsworth. Greer, I. A., Nelson-Piercy, C., & Walters, B. (2007). Maternal medicine: Medical problems in pregnancy. Edinburgh: Churchill Livingstone. Kail, R. V., & Cavanaugh, J. C. (2013). Human development: A life-span view. Belmont, Calif: Wadsworth Cengage Learning. Newman, B. M., & Newman, P. R. (2012). Development through life: A psychosocial approach. Belmont, CA: Wadsworth Cengage Learning. Sigelman, C. K., & Rider, E. A. (2011). Life-span human development. Belmont, CA: Wadsworth, Cengage Learning. Wehby, G. (2006). Prenatal Care Utilization and Its Effects on Infant Health in Samples of Normal Versus Abnormal Births from South America. ProQuest. Read More