Human Genetics Lecture 06: Variation in Chromosome Structure

Play an AI-generated podcast conversation about this lesson

What are the four basic types of chromosome rearrangements?

Duplications, Deletions, Inversions, Translocations

How can the structure of chromosomes be altered in terms of the total amount of genetic information?

Deletions/Deficiencies and Duplications

What is a chromosome duplication and what causes it?

A mutation where part of the chromosome is doubled with extra genetic material; caused by abnormalities in crossing over during meiosis.

What are the two types of duplications based on their orientation and location?

Tandem (adjacent) and Displaced (some distance from the original segment), in the same or inverted orientation. Signup and view all the answers

What is Charcot-Marie-Tooth disease (type 1A) caused by in humans?

A small duplication on the short arm of chromosome 17 Signup and view all the answers

What is the difference between nonreciprocal and reciprocal translocations?

Nonreciprocal translocations involve one-way movement of genetic material between chromosomes, while reciprocal translocations involve a two-way exchange. Signup and view all the answers

What genetic alteration is associated with Chronic Myeloid Leukemia?

Chronic myeloid leukemia is associated with the Philadelphia chromosome, resulting from a reciprocal translocation between chromosomes 9 and 22. Signup and view all the answers

Explain the difference between terminal and interstitial deletions.

Terminal deletions involve the loss of a piece without the centromere, while interstitial deletions involve breaks at two places with reattachment of the remaining pieces. Signup and view all the answers

How do inversions and translocations in cancer contribute to the disease?

Inversions and translocations in cancer may disrupt tumor-suppressor genes or create fused proteins that stimulate cancer processes. Signup and view all the answers

How do deletions in cancer contribute to unregulated cell division?

Deletions in cancer may result in the loss of tumor-suppressor genes, which promotes unregulated cell division. Signup and view all the answers

What are some phenotypic consequences of deletions, especially larger ones, in humans?

Imbalances in gene products, Pseudodominance, Haploinsufficiency Signup and view all the answers

Provide an example of a syndrome in humans caused by a deletion on a specific chromosome.

Cri-du-chat syndrome caused by a deletion on the short arm of chromosome 5 Signup and view all the answers

Types of Chromosome Rearrangements

The four basic types are duplications, deletions, inversions, and translocations.

Chromosome Duplications

A mutation that doubles a segment of a chromosome, causing extra genetic material.