Chromosomes are made of protein and a single molecule of deoxyribonucleic acid (DNA) which contains the specific instructions and makes their child a unique living being. Most human cells contain 23 pairs of chromosomes (46 in total). Genes are basic physical and functional units of heredity. They are made up of DNA and occur in pairs (one from each pair is inherited from each parent).

Chromosomes are thread-like structures found within the nucleus of a cell that carry the codes for inherited traits.

Genes are sections of chromosomes and the basic units of heredity.

Most of the human cells have 23 pairs of chromosomes which are 46 in total. Egg cells and sperm cells have half of that number. When they are fertilized they will create a zygote that has 46 chromosomes, 23 from each parent.

Human cells- 23 pairs of chromosomes (46 in total)

Egg cell and sperm- 23 chromosomes

Female cells contain X chromosomes, while male cells have X and Y chromosomes. Since egg cells and sperm cell contain half the chromosomes of other cells, they can only have one sex cell. So an egg cell will contain X chromosome, while sperm can contain either X or a Y chromosome.

Female cells- X chromosome

Male cells- X and Y chromosome

Chorionic villus sampling (CVS) is also called chorionic villus biopsy. It is a prenatal test that involves taking a sample of tissue from the placenta in order to test for chromosomal abnormalities and certain genetic problems. Usually it is done around the eighth week of fetal development.

Pregnant women can consider having CVS around the eighth week of fetal development.

If you cross a brow hair parent (dominant) with blond hair parent (recessive), a child will have a dominant phenotype which is heterozygous (Hh).

A brown haired person in this case has dominant phenotype which is heterozygous (Hh).

Genetic research is the study of human DNA. The main role is to find out what genes and environmental factors contribute to diseases. When the cause of some disease is found, it is easier to detect disease. Also, it can be treated better or can even be prevented. Many conditions and diseases are related to genes and caused by issues with multiple genes in combination with our lifestyle and environmental factors. So, understanding it will help us improve our health.

The main role of genetic research is to find out what genes and environmental factors contribute to diseases in order to detect them easier.

Genetic counseling and gene therapy can help prevent or cure many diseases that didn’t seem possible before. Humans have around 25,000 genes per cell, and mutation or change of any of those genes can cause disease. Those mutations can be inherited or can occur spontaneously. Gene therapy is basically the manipulation of genes to fight or prevent diseases (using “good” genes to fight harmful “bad” genes). It has great potential to eliminate and prevent hereditary diseases, for example cystic fibrosis or hemophilia. Also, it is used as a cure for heart disease, AIDS and cancer. Gene therapy is still being investigated but its potential in medicine is existing and hopes for its performance are high.

Gene counseling and gene therapy can help prevent or cure many diseases that didn`t seem possible before. See the explanation for more details.