A woman who sought genetic counseling is found to be heterozygous for a chromosomal rearrangement between the second and third chromosomes. Her chromosomes, compared to those in a normal karyotype, are diagrammed to the right. What kind of chromosomal aberration is shown?

Key Concepts

Chromosomal Aberrations

Chromosomal aberrations refer to structural changes in chromosomes that can affect genetic information. These changes can include deletions, duplications, inversions, and translocations, which may lead to genetic disorders or impact an individual's health. Understanding these aberrations is crucial for interpreting genetic counseling results and assessing potential risks.

Heterozygosity

Heterozygosity describes the presence of two different alleles at a specific gene locus on homologous chromosomes. In the context of chromosomal rearrangements, being heterozygous means that one chromosome carries the rearrangement while the other is normal. This genetic variation can influence the expression of traits and the likelihood of passing on genetic conditions.

Karyotype Analysis

Karyotype analysis is a laboratory technique used to visualize an individual's chromosomes, allowing for the identification of chromosomal abnormalities. By comparing the karyotype of an individual with a standard reference, geneticists can detect variations such as rearrangements, which are critical for diagnosing genetic disorders and informing treatment options.