Cystic fibrosis is an inherited disorder involving cell membranes, caused from too much
mucus getting clogged in the lungs. This causes breathing to get more difficult overtime,
which unfortunately lowers the person’s life expectancy. Like most other characteristics,
this is caused by alleles; faulty ones to be specific. There is a 1 in 2 chance of cystic
fibrosis being passed over from one parent and carrying it, a 1 in 4 from both parents
and having the disorder, and a 1 in 4 chance for it to not get passed on at all.
Huntington’s disease is an inherited disorder that stops the brain from working
overtime, and leads to death after roughly a 20-year period. This is caused by a faulty
gene due to the brain getting damaged overtime. Huntington’s disease has a 50% chance
of being passed down from parents, and another 50% for it not. There is a small chance
to develop Huntington's disease without having a history of it in your family, but this is
usually just because one of your parents was never diagnosed with it.
Polydactyly is an inherited disorder that causes the person to grow extra fingers or toes.
Unlike some other characteristics, this is caused by the dominant allele; meaning
parents need only one to pass it on to their offspring, also a 50% chance of happening. It
can be seen in around 1 in 500-1000 babies born and overall is harmless. To treat it,
surgery would need to remove the finger or toe.
Sickle cell anaemia is an inherited disorder that makes it so red blood cells can’t carry
enough oxygen around the body. Red blood cells are usually round and have a wide
surface area, so they can move and contain oxygen more efficiently. In sickle cell
anaemia however, some red blood cells have a more sickle or crescent-like shape. These
sickle cells also become rigid and sticky, which can slow down or prevent blood flow
entirely. There is no known cure and if both parents have the sickle cell trait, there
would be a 25% chance of it getting passed down to their offspring.
