Why would it be beneficial toknow about the human geneticcode?

• Exam next Friday

1990-2003• Project set out to sequence the entire human genome

• Identify all 20,000-25,000 human genes• Bank all results of human genetics

Scientists have now set out to figure outwhat each of the genes in the genomedo, and how they interact in a cell.

• What protein does each gene make• What does that protein do in your body• Does gene turn on and off

Pedigree charts-

Look at family history to see who in afamily is affected by a disease and whocarries a disease.• Used to tell potential parents the likelihood that their child will have a disease

A karyotype is a method of looking atall of a person’s DNA to look forchromosomal abnormalities• DOES NOT show defective genes• used to look for chromosome defects

• Down’s syndrome• Kleinfelter’s syndrome (XXY)

Some genes are located onchromosome 23 (X or Y)- sex chromosomesThose genes are sex-linked.(other 44 chromosomes called autosomes)

• If mother is double recessive, male child (XY) MUST show that disease, because his X chromosome came from mom (ex. Colorblindness, hemophilia)

What cell organelle gives you the energyyour body needs to operate?

This organelle also has its own DNA.• Its DNA also replicates when cells divide

Each time DNA replicates, a SMALL bitis lost on the ends.

Therefore, each new cell’s mitochondriahave a bit less DNA.

This means they function less efficiently

Recent developments in science- WHY DO WE AGE?

As mitochondria work less efficiently, ourcells do not get the energy they need tofunction• Causes cell death• Causes body to age!!!

In a sex-linked recessive trait, if mom has the trait, is it possible for her son to not have it?

• (lab) Karyotyping • Exam next Friday