Question 6: Matching the Evidence

So here comes the question before the finale, how do we match the evidences collected with the suspected victims reported missing? 

From the bone remains and skull fragments obtained by The Dental Tooth Fairies from the crime scene, DNA samples of the victims are able to be extracted and collected. After that, we are able to generate DNA fingerprints for the victims via a technique called DNA Profiling. 

(Watch the above video to get a clearer picture on DNA fingerprints and how they are generated)

* Note : All characters in this publication are fictitious and any resemblance to real persons, living or dead, is purely fictional. All photos published are credited and used solely as examples. All DNA samples are purely fictional.

Looking into Adi Hartono and Herman Hartono's case, we know that they are paternally linked. But how do we prove that? And how can we prove that the skull fragments and bone remains belong to them?


Based on the evidence found in the crime scene, we can conclude that one of the bone remains belonged to a young male adult. From the DNA sample extracted from it, we are able to create a DNA fingerprint of the young male adult, as seen below. Finally in order to confirm that the bone remains actually belonged to Adi Hartono, we make another DNA fingerprint based on any DNA samples collected from his room, such as hair, saliva, skin, blood and even semen too, or maybe even from his family doctor whom have his blood samples. If the DNA sample from the crime scene and DNA sample of Adi Hartono matches 100%, then we can conclude that the bone remains actually belonged to Adi Hartono.

Using the same method, we can do the same for the other DNA sample found on the bone remains of the male adult. Assuming the same procedures have been conducted, DNA sample of the male adult bone remains is compared with the DNA sample of the Herman Hartono. If both DNA fingerprints matches, then we can conclude that the bone remains belonged to Herman Hartono.


Ok, now to confirm whether Adi Hartono and Herman Hartono are biological father and son. As shown below, we have 3 DNA fingerprints prepared by the Dental Tooth Fairies. The extra DNA fingerprint is obtained from a DNA sample collected from Ms. Hartono (Adi Hartono's biological mother, Herman Hartono's wife).

Observe the DNA bands carefully.

From your observation, you will be able to find that some of the DNA bands from Adi match with Herman's DNA bands and the rest of Adi's DNA bands match with his biological mother, Mrs. Hartono's DNA bands. It can be concluded that all DNA bands inherited in a child's profile are inherited from his parents. Hence, we can conclude that Adi Hartono and Herman Hartono are blood related and Herman Hartono is Adi Hartono's biological father.

As we know, there was DNA profiling pattern that matched one living twin (Tanya Rosilawati). Since identical twins have almost identical DNA, we can conclude that the child’s jaw remains belong to Tanya’s twin, Anya Suriati.

How are twins formed?
During sexual intercourse, a single sperm meets a single egg. The cells divide and expand as the zygote travels to the uterus. Occasionally, for reasons unknown, the cell divides into two parts that develop as two distinct individuals, creating monozygotic twins. Technically, we consider the reason for the split as mutation.

Identical twins’ DNA varies?
Research in 2005 found that all identical twins may actually differ genetically from their partners to some degree. Geneticist Carl Bruder et al reported results of a study of nineteen identical twins. The team found relatively common, but small, differences in the DNA of these identical twins. For some twins, one twin had a different number of copies of a given gene than his twin. This condition is called 'copy number variant' or CNV.

Fun Facts about GENES!


Theoretically, identical twins develop from monozygotic cell division will share the same genetic profile. However, science and technology in this 21st century has proven it to be not quite accurate in some cases. In February 2008, geneticist Carl Bruder of the University of Alabama at Birmingham, reported results of a study of nineteen identical twins. Bruder and his team discovered relatively common, but small, differences in the DNA of these identical twins. What happens is one twin’s DNA differed from the other at various points on their genomes, i.e.one twin had a different number of copies of a given gene than his twin. This genetic state is known as 'copy number variant' or CNV.

How is it so? At first when the fertilized egg is divided into two, identical genetic profile of 100% similarity is seen. The initial divided fertilized egg will form two cells which mean at the beginning the DNA is identical. However, in order for the egg cell to form into embryo, millions or even trillions of cell division must occur. In between the process of cell division, the cells can make mistakes in the number of copies of a given gene passing to the daughter cells, which is the so-called mutation. However, such mutation could not actually being spotted upon DNA analysis. Hence, that’s how twins sometimes can reach different numbers of copies of a gene and why some identical twins’ DNA are almost identical but not fully identical.





As you can see in this picture, you can note the slight difference between each twins’ DNA profile. For individuals in B and C, you can see that there are more similarities in the DNA profiling whereas sometimes due to CNV, you can expect results in A and D.



References

http://www.livescience.com/4833-identical-twins-dna-varies.html
http://www.wonderquest.com/twins-dna.htm
http://multiples.about.com/od/funfacts/a/Identical-Twins-And-Dna.htm