How is genetic information inherited?
Humans inherit 23 chromosomes from each of their parents. Sperm and eggs cells each contain 23 chromosomes, which combine during reproduction to give the offspring a total of 46.
Forty-four of these chromosomes are identical in men and women - the autosomes. The remaining two are called sex chromosomes, and are designated X and Y. Women inherit two X chromosomes and men inherit one X-chromosome from their mother and one Y-chromosome from their father.
The genetic information we inherit is never exactly the same as that of our parents. During the production of egg and sperm cells, the chromosomes exchange segments in a process known as recombination, which produces new combinations of genes.
These gene combinations give us similarities to our mother and our father but are a new mosaic of our maternal and paternal genes.
What are gene variants?
In biology class, we learnt that the DNA we inherited from our parents determines our physical traits like eye and skin color. Now with the field of nutrigenomics – the study of how our genes influence our nutrition, fitness + more – we can confidently predict how our DNA affects a whole lot more than just our physical appearance.
Humans are made up of mostly the same genes. It's the variations in these gene that define the result of how it will affect our bodies.