Prenatal Development and Genetic Engineering

Posted on Mar 3, 2025 in Biology

Non-Hereditary Diseases

Non-hereditary diseases can arise from various factors during pregnancy and birth:

Problems During Pregnancy

  • Thalidomide: A drug administered in the 1960s to pregnant women for anxiety, which caused malformations or absence of limbs in many children born in Europe.
  • Rubella: Pregnant mothers contracting rubella from children (a usually benign disease) can transmit the virus to the fetus, causing significant harm. To prevent this, all girls are vaccinated at 12 years old to develop antibodies.
  • Radioactivity: Exposure to radiation during pregnancy.

Problems at Birth

  • Lack of Oxygenation: Decreased oxygen concentration in the fetal blood can lead to irreversible brain damage.

Prenatal Diagnosis of Hereditary Diseases

  • Ultrasound: Used to study the anatomy, sex, location, and size of the fetus.
  • Amniocentesis: A test performed to study the karyotype of fetal cells, checking for chromosomal diseases.

Twins

  • Identical Twins: Result from a single egg fertilized by a single sperm. The zygote duplicates its chromosomes and divides into two zygotes, resulting in genetically identical individuals.
  • Fraternal Twins: Develop from two separate eggs fertilized by two separate sperm, creating two distinct zygotes.
  • Siamese Twins: Occur when the division of identical twins is incomplete, leaving the two fetuses joined at some point.

Genetic Engineering

Genetic engineering involves the possibility of locating a gene on a chromosome, isolating it, and transferring it to another organism, even of a different species. An organism with a gene from another species incorporated into its genome is known as a transgenic organism. This includes animals, plants, and bacteria.

Genetic engineering is any intentional and directed change in the genetic information of cells. The development of genetic engineering opens up possibilities for:

  • Changing damaged genes for healthy ones (in the DNA of the egg or sperm).
  • Potentially curing diseases such as hemophilia, Down syndrome, etc.
  • Using bacteria as factories to produce chemicals, such as insulin.

For example, bacterial production of insulin involves introducing the human insulin gene into the bacterial DNA. This modified bacterium and its offspring will then produce insulin.

Applications of Transgenic Organisms

  • Pharmaceutical Products: Insulin, growth hormone, etc.
  • Special Foods: Low-cholesterol meat, gluten-free cereals, etc.
  • Organ Transplants
  • Agriculture and Livestock: Crop resistance, faster growth.

Risks of Genetically Modified (GM) Foods

  • Loss of genetic diversity.
  • Accidental transfer of genes to wild species.
  • Adverse health effects, such as allergies.
  • Monopoly by large seed companies.

Consequences of Human Genome Knowledge

  • Characters are known to be in the genes of chromosomes.
  • There are 3 billion nucleotides and approximately 20,000-25,000 genes (not 100,000).
  • The human genetic code is being deciphered.
  • Genes from other organisms are viable for humans.
  • Legislation is needed to protect human privacy, addressing issues such as:
    • Job security.
    • Medical and life insurance.
    • Ethical concerns about selecting a baby’s sex and preventing diseases, potentially leading to “designer babies.”