Question

Compare partial monosomy with haploinsufficiency.

Short answer

Answer: The main differences between partial monosomy and haploinsufficiency are the causes and the degree of impact on the phenotype. Partial monosomy results from a structural change in the chromosome that causes the loss of some genetic material, typically leading to more severe phenotypic effects. On the other hand, haploinsufficiency occurs when one functional allele of a gene is insufficient to maintain proper function and regulation, impacting only one specific gene.

Step-by-step solution

Define Partial Monosomy

Partial monosomy is the condition where an individual has a missing portion of a single chromosome, resulting in the loss of some genetic material. This can lead to various health problems and developmental issues, depending on the specific genes affected.

Define Haploinsufficiency

Haploinsufficiency is a situation where having one functional copy of a gene is not enough to produce the normal phenotype. In other words, the presence of one functional allele is insufficient to maintain the proper function or regulation, typically resulting in a dominantly inherited disorder.

Compare Similarities

Both partial monosomy and haploinsufficiency involve altered function or regulation of genes caused by a reduction of the normal gene dosage. In both cases, the altered dosage can have significant effects on an individual's phenotype, leading to various health issues and developmental disorders.

Compare Differences

The main difference between partial monosomy and haploinsufficiency is the cause of the altered gene dosage. Partial monosomy results from a structural change in the chromosome, leading to the loss of some genetic material. On the other hand, haploinsufficiency is caused by the presence of one functional allele being insufficient to maintain proper function and regulation. Additionally, partial monosomy typically leads to more severe effects on the phenotype, as it involves the loss of several contiguous genes, whereas haploinsufficiency impacts only one specific gene.

Provide Examples of Partial Monosomy

One example of partial monosomy is Cri-du-Chat Syndrome. This rare genetic disorder is caused by the deletion of a portion of chromosome 5. Symptoms include intellectual disability, a high-pitched cry, and specific facial features. Another example is 1p36 Deletion Syndrome, which is caused by the loss of a portion of chromosome 1. This can lead to moderate to severe intellectual disabilities, slow growth, and various health issues, including heart and kidney problems.

Provide Examples of Haploinsufficiency

An example of haploinsufficiency is Marfan Syndrome, an autosomal dominant disorder caused primarily by a mutation in the fibrillin-1 (FBN1) gene. People with Marfan Syndrome often have skeletal and connective tissue abnormalities, as well as cardiovascular issues. Another example is the tumor suppressor gene TP53, which is associated with Li-Fraumeni Syndrome. In this case, one mutant copy of TP53 leads to increased susceptibility to various types of cancer due to insufficient tumor suppression.