DNA is a key piece of evidence in many rape cases, but when it comes to identical twins, police in the U.K. are finding this genetic material useless. In light of this conundrum and not knowing which twin could potentially be the rapist, authorities charged both men.
Identical twins might have the same DNA but they do have another feature that could be used to tell them apart -- their fingerprints. It is unclear if fingerprint evidence will be used in a rape case where both twins have been charged at this point. (Image: Shutterstock.com.)
Mohammed and Aftab Asghar entered separate pleas while at court in Berkshire this week on charges rape, which allegedly took place in November 2011, the Daily Telegraph reported.
Although both of the 22-year-olds were charged, prosecutors are still wrestling with how to move forward.
"It is an unusual case. They are identical twins. The allegation is one of rape," prosecutor Sandra Beck told the Telegraph. "There is further work due...It may mean that only one of the defendants faces trial."
Although their DNA might not be useful in the case, they pair does have different fingerprints that could provide evidence. The New York Times explained in 2009 how different fingerprints form in identical twins:
Researchers have found that identical twins have a very high correlation of loops, whorls and ridges, but a review study last year in Circulation Research examining how complex structures like the circulatory system develop says that “the detailed ‘minutiae’ — where skin ridges meet, end or bifurcate — are different even between identical twins.” Even twins that develop from one zygote occupy different positions in the womb, and the variations are enough to make a difference.
At the crucial stage of development, the study explains, ridges are thought to form as compressive stresses develop in the dermal cell layer of the skin, sandwiched between the epidermis and the subcutaneous tissue. “Like the buckling of land masses under compression,” the study continues, regular ridges form to relieve the stress.