Question

Why might a small deletion be viable if heterozygous?

How does a small duplication result in a phenotype when heterozygous?

Larger deletions are typically not viable even as heterozygotes. Why? And what genetic term is associated with this phenomenon?

Answer 1

Answer:

Why might a small deletion be viable if heterozygous?

• Heterozygous genotypes consists of 2 different alleles at a single locus. In case of heterozygous small deletion. A small deletion may not include number of genes that are important for the functioning of a cell. Therefore, a small deletion could be viable.

How does a small duplication result in a phenotype when heterozygous?

Duplication of certain genetic elements may act as mutations.and elicit new phenotypes.Duplications can cause doubling of chromosomal segments (or increase in copy number of a particular chromosomal region) and result in the formation of unpaired loops. One example of a small duplication in heterozygous resulting in a new phenotype is bar shaped eye in Drosophila present in flies heterozygous for a duplicated gene.

Larger deletions are typically not viable even as heterozygotes.  Why? And what genetic term is associated with this phenomenon?

A large Heterozygous deletion causes a hemizygous (only one copy present) state in a gene and this could be lethal since regions that are crucial for functioning are affected.