Copy Number Variations

Definition

Copy number variations (CNVs) are structural genomic alterations that result in the duplication or deletion of sections of DNA, leading to differences in the number of copies of specific genes or genomic regions between individuals. These variations can impact gene dosage and contribute to phenotypic diversity, disease susceptibility, and evolutionary processes.

5 Must Know Facts For Your Next Test

1. CNVs can span a few hundred base pairs to several million base pairs and are a significant source of genetic diversity in populations.
2. These variations have been linked to various human diseases, including autism, schizophrenia, and certain cancers.
3. Technologies like array comparative genomic hybridization (aCGH) and next-generation sequencing (NGS) are commonly used to detect CNVs.
4. The distribution of CNVs in the genome is not random; certain regions are more prone to these variations due to factors like repetitive sequences.
5. Understanding CNVs is crucial for personalized medicine, as they can influence an individual's response to drugs and susceptibility to diseases.

Review Questions

• How do copy number variations contribute to genetic diversity among individuals?
  • Copy number variations contribute to genetic diversity by causing differences in gene dosage between individuals. When sections of DNA are duplicated or deleted, it alters the number of copies of specific genes present in the genome. This can lead to variations in traits and phenotypes among individuals, which is a key element in understanding population genetics and evolution.
• What role do technologies like array comparative genomic hybridization play in studying copy number variations?
  • Array comparative genomic hybridization (aCGH) and next-generation sequencing (NGS) are critical tools for identifying and analyzing copy number variations. These technologies allow researchers to detect both large-scale and subtle changes in DNA copy numbers across the genome. By using these methods, scientists can gain insights into how CNVs relate to disease mechanisms and individual variability in traits.
• Evaluate the implications of copy number variations on personalized medicine and disease susceptibility.
  • Copy number variations have significant implications for personalized medicine as they can influence an individual's risk for developing certain diseases and their response to treatments. By understanding a person's unique CNV profile, healthcare providers can tailor medical interventions based on their genetic makeup. This approach helps in predicting disease susceptibility and improving treatment outcomes by considering the genetic factors that affect drug metabolism and effectiveness.

Related terms

Single Nucleotide Polymorphism (SNP): A single base pair change in the DNA sequence that can contribute to genetic variation among individuals.

Genomic Instability: An increased tendency for the genome to acquire mutations, which can lead to cancer and other diseases.

Structural Variants:

Larger scale alterations in the genome structure, including inversions, translocations, and CNVs, that can influence gene function.