Absolutely.
carrier
Cystic fibrosis is the most common life threatening disease in the UKOne in 25 people have the cystic fibrosis gene in them (but may not have the disease). Most people aren't even aware that they carry the gene. If two people who have the gene reproduce, the odds that they have a child with cystic fibrosis is 1 in 4. The chance that they will have a child who carries the gene but doesn't have the disease is 2 in 4 (half). The chance that they have a child who does not have the disease or carry the gene is 1 in 4.
Yes, as long as you carry the gene you will, in some stage of your life develop the disease.
25% will have the disease if both parents carry the gene. 50% will be carriers. 25% will be neither.
Yes, because it is "autosomal recessive hereditary disorder".
Yeah. You can still carry the gene of the reddish brown hair.
Yes, Celiac Disease can develop at anytime. For a person to develop Celiac Disease, one must carry the gene. The gene can remain "off" or it can turn "on". You can have the gene but never experience any celiac disease symptoms. Something has to trigger the gene for a person to start developing problems. My mom didn't have symptoms until she was in her 30's. Before that, she never had any problems eating grains.
because he has no dominant gene to make the trait
It's called a "Punnet square".
If you carry the sickle cell gene, it doesn't really mean much as far as your own personal health goes. Except that you are less likely to get malaria. However, if you decide to have kids, and whoever you mate with also carries the sickle cell gene (not the full blown disease/gene) , your child has a chance of having sickle cell disease (full blown).
Let's do a Punnit Square. T T T TT TT t Tt Tt T is normal, and the little "t" is the recessive gene (which is being carried by one parent). Since one parent is recessive, you can see that there's a 50% chance that the offspring will have the recessive gene as well. However, note that without any straight "tt" result, there is a 0% chance that the offspring can express the Tay Sachs disorder.
Identifying the faulty Gene. Identifying the faulty Gene that causes the disease.