DNA left at a crime scene could be used in the future to build up a picture of an offender’s face, it was revealed tonight.
A first step towards genetic
mugshots has been taken by researchers in the US who link specific DNA markers with face shape. To identify the genes, they focused on known mutations(突變) that cause changes of the face and head. Normal versions of these genes were found to influence individual features. For instance, one gene affected the lips, another the shape and configuration of bones around the eyes, and a third the appearance of the mid-face and skull. In total, 20 genes had “significant effects” on facial appearance.
Lead scientist Professor Mark Shriver, from Pennsylvania State University, said: “We use DNA to match to an individual or identify an individual, but you can get so much more from DNA. Currently we can’t go from DNA to a face, or from a face to DNA, but it should be possible.” The implications are far reaching, raising the possibility of creating a data bank of facial types based on genetic markers. DNA from a crime scene could then be used to produce a rough image of the face of an offender or victim. Such genetic mugshots may be more reliable than computer-generated “e-fits” based on witnesses’ recollections. Other uses of the technique might include proving the identity of fathers in paternity cases, or visualising our remote ancestors from fossil DNA.
The scientists wrote in the online journal Public Library of Science Genetics: “Such predictive modelling could be forensically useful; for example, DNA left at crime scenes could be tested and faces predicted in order to help to narrow the pool of potential suspects. Further, our methods could be used to predict the facial features of descendants, deceased ancestors, and even extinct human species. In addition, these methods could prove to be useful diagnostic tools.” The team developed a model which first established a range of physical face shapes from people of mixed West African and European ancestry from the US, Brazil and Cape Verde. Measurements were taken of thousands of point co-ordinates on grids placed over 3D images of the faces.
Statistical methods were then used to determine the relationship between facial differences and the effects of gender, ethnic ancestry and individual gene variants.
小題1:The underlined word “mugshots” in the second paragraph most probably means _________.
| A．different faces | B．characteristics | C．pictures of faces | D．genders |
小題2:What can be inferred from the passage?
A. DNA has been used to build up a picture of an offender’s face.
B. It may be much easier to catch criminals with the help of DNA.
C. In all, 20 genes had “significant effects” on facial appearance.
D. One gene can affect more than one part of your face.
小題3:According to Professor Mark Shriver, we know_________.
| A．they can merely match to an individual or identify an individual |
| B．there is a possibility of going from DNA to a face |
| C．DNA could be used to produce a rough image of an offender’s face |
| D．this technology is more reliable than computer-generated “e-fits” |
小題4:What is the most possible title of the passage?
| A．Creating a data bank of DNA |
| B．Recognizing the DNA of criminals |
| C．Predicting the location of offence using DNA |
| D．Building image of offender’s face from DNA |
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