I have read that mature red blood cells (MRBs)do not have DNA. So I am curious why crime scene technicians collect blood. Is it to collect and amplify segments of white blood cells?
There's still white blood cells with DNA.
Some forensic blood tests are:
Conventional serological analysis:
- Analysis of the proteins, enzymes, and antigens present in the blood, for general doctor tests: (black/white/drunk/stoned/heroin addict/polio vaccinated/hiv pos...)
Restriction Fragment Length Polymorphism (RFLP) DNA :
- Direct analysis of certain DNA sequences present in the white blood cells. This method also usually requires a "large" sample size to obtain significant results.
Polymerase Chain Reaction (PCR) DNA :
- Analysis of certain DNA sequences that have been copied multiple times to a detectable level.