Indicate the expected number of Barr bodies in interphase cells of individuals with Klinefelter syndrome; Turner syndrome; and karyotypes 47,XYY, 47,XXX, and 48,XXXX.

Key Concepts

Barr Bodies

Barr bodies are inactivated X chromosomes found in the cells of individuals with more than one X chromosome. In females, typically one X chromosome is active while the others are condensed into Barr bodies. This process is crucial for dosage compensation, ensuring that gene expression levels are balanced between males and females.

Klinefelter Syndrome

Klinefelter syndrome is a genetic condition in males characterized by the presence of an extra X chromosome, resulting in a karyotype of 47,XXY. Individuals with this syndrome typically have one Barr body in their interphase cells, as one X chromosome is inactivated while the other remains active.

Turner Syndrome

Turner syndrome occurs in females who have only one X chromosome, resulting in a karyotype of 45,X. Since there is only one X chromosome present, there are no Barr bodies in interphase cells, as there are no additional X chromosomes to inactivate.