What is touch DNA?

What is touch DNA?

• A. DNA obtained from skin cells transferred onto objects like weapons or gloves.
• B. DNA degraded beyond study.
• C. DNA that touches the surface of the genome.
• D. DNA recovered only from blood samples.

Answer: (C)

Touch DNA refers to genetic material left behind on a surface when someone handles or touches it, typically from shed skin cells. This means DNA can be recovered from objects that were touched, such as weapons or gloves, even when there’s no visible fluid present. The description about DNA “touching the surface of the genome” isn’t a real way to describe how DNA is deposited or analyzed; the genome is inside cells, and DNA isn’t described as contacting it in that sense. Also, touch DNA isn’t restricted to blood samples; it often comes from skin cells or other trace material transferred by contact. In practice, touch DNA can be present in very small amounts and requires careful collection and sensitive analysis.

Touch DNA refers to genetic material left behind on a surface when someone handles or touches it, typically from shed skin cells. This means DNA can be recovered from objects that were touched, such as weapons or gloves, even when there’s no visible fluid present. The description about DNA “touching the surface of the genome” isn’t a real way to describe how DNA is deposited or analyzed; the genome is inside cells, and DNA isn’t described as contacting it in that sense. Also, touch DNA isn’t restricted to blood samples; it often comes from skin cells or other trace material transferred by contact. In practice, touch DNA can be present in very small amounts and requires careful collection and sensitive analysis.