Viewing a single comment thread. View all comments

Furrypocketpussy t1_j4j1fbt wrote

Reply to comment by CrateDane in Can a recessive gene become a dominant gene? If so, how long would it take? by Pretend-Recover-4418

Alleles are variants of genes. And no, still talking about recessive. Sickle cell, as an example, is a recessive disease and is still expressed in heterozygotes

1

CrateDane t1_j4kg8y3 wrote

Well no. Full-blown sickle cell disease only affects homozygotes, and as such is considered recessive. But the heterozygotes do still have a different phenotype than either homozygote in some ways. That means in those respects the allele is not recessive at all. When it comes to malaria resistance, it's more of a dominant allele.

0

Furrypocketpussy t1_j4n4ueo wrote

Idk what mental gymnastics you going through to term a recessive disease "dominant". Sickle cell heterozygotes are just in between full blown sickle cell and normal, thats just codominant expression but the disease is still recessive because if it was dominant then heterozygotes would have full sickle cell. Need to inform yourself before making bogus claims online

https://medlineplus.gov/genetics/condition/sickle-cell-disease#:~:text=Inheritance&text=This%20condition%20is%20inherited%20in,and%20symptoms%20of%20the%20condition.

1

CrateDane t1_j4n6mu3 wrote

Read your own source:

>This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations.

Your source does explain that it gets complicated when there are, for example, two different kinds of mutations in the two copies of the gene. That obviously goes beyond the simple categorization of recessive vs. dominant.

Other sources make the definition even clearer, like this:

>sickle cell anemia, which is defined as homozygosity for the sickle hemoglobin (HbS) gene (i.e., for a missense mutation [Glu6Val, rs334] in the β-globin gene [HBB])

1