Your cousins aren’t just called your cousins for no reason. There are actually quite a few hereditary traits which could create similarities with cousins. Read ahead to understand how genes pass on and how much DNA you share with your blood relatives.
What are Genes
Genes are made of DNA. They exist throughout your body. They are like a set of instructions that determine the organism's appearance, how it acts, behaves and survives. Genes are a part of DNA which are responsible for making proteins. Many strands of DNA along with genes make up chromosomes which are located in the nucleus of cells.
Similarities among Cousins
Take a look at the family tree to understand how many genes you actually may have in common with your cousins.
Your first cousins could have about 12.5% of the genes that you have. This means that 87.5% of the genes between you and your cousins.
A rare phenomenon seen in some families known as elusive double cousin is where two siblings of one family reproduce with two siblings of another family. This causes the children to be related to each other through both parents. Double cousins share the same grandparents and are genetically equal to half siblings. They share almost double of the genetic material seen in first cousins.
How Genes are Passed on
Through generations, genes are shuffled and reshuffled. Half of your genes come from your mother and the other half from your father. In turn, your parents inherited their genes from their parents. This means that about one quarter of your genes come from your grandparents. Let’s look at how this works. Each egg and each sperm contains 23 chromosomes each. When they meet during conception, they combine to become a full component with 46 chromosomes. This forms the genetic blueprint of the baby. Out of the 23 chromosomes, one of them is the sex chromosomes. This means that the gender of the baby is determined at conception. Each egg contains an X chromosome. While the sperm can contain either an X or a Y chromosome. If two X chromosomes combines, the baby is a girl, whereas if one X and Y chromosomes combine, the baby is a boy.