Mutations

These should be:

Cystic Fibrosis (deletion/missense)

Infantile Tay-Sachs (point mutation on chromosome #15)

Achondroplasia (point mutations)

How do the mutations change the properties of the protein(s) translated from the DNA, and why that results in disease symptoms?

Mutations initially involve a point mutation or deletion of one or more nucleotides, and change the DNA. When the DNA is transcribed and the RNA is processed by ribosomes, changes to the DNA means that the proteins produced are going to be different, resulting in a change in phenotype. There are 20 different amino acids that make up a protein. Some are hydrophilic (polar/water attracting), while others are hydrophobic. A protein is composed of these amino acids, and the sequence of these amino acids determines the folding/structural shape of a protein. While hydrophilic amino acids are exposed to the outside of the protein, hydrophobic amino acids are buried inside of the protein giving the protein its structural shape. The shape of the protein may determine the function/active site of the protein, by bringing certain amino acids closer together.

If there is a mutation in the RNA/DNA strand this will change (1 or more) amino acids, this means that

1) An amino acid that is polar may be substituted by a non-polar one, changing the (structure) - the way the protein is folded. This may bring a different sequence of amino acids to make up the functional site which may cause the protein to be non-functional or produce a different chemical than it should.

Or 2) the amino acid substituted/deleted may be one that makes up part of the active/functioning site.

So in summary, a mutation technically only affects DNA...but changes to the DNA will sometimes mean a slightly different protein is produced.

Wow, Bio_Man you never seem to let me down
 

Thank you so much!