MISSING PERSONS

• Jurisdiction: Australia

MISSING PERSONS

Overview ....................................................................................................... [80A.2700]

Family tree .................................................................................................... [80A.2720]

Comparison of DNA profiles ......................................................................... [80A.2740]

[80A.2700] Overview

In a typical missing person case, where the identity of a dead body is in question, both parents' genotypes are unknown in the second proposition (in which the alleged parents are not the parents). The probability of the child inheriting the relevant allele from a randomly selected person must be calculated for both parents under the defence proposition (ie, that the dead body is not that of the missing person).

In some cases, several relatives are available for typing in addition to the parents. In the following example, information has been provided in relation to DNA profiles obtained from an unidentified, decomposing body and the family of a missing woman.

Missing woman	genotype = U
Husband of missing woman	genotype = H
Children of missing woman	genotypes = X, Y
Mother of missing woman	genotype = M
Unidentified body	genotype = B

No information is available about the genotype of the missing person's father, who is deceased.

[80A.2720] Family tree

Mother - Deceased father

|

Missing woman - Husband

|

Child1 Child 2

[80A.2740] Comparison of DNA profiles

It is assumed that the mother is the biological mother of the missing woman and that the children are the biological children of the missing woman and her husband.

Table 2 contains the DNA profile information supplied. From this information, the possible genotypes of the missing woman can be deduced at each locus. (It is assumed that there are no mutations in any of the meioses depicted in the family tree above.) The genotype of the body at each locus is one of the possible genotypes of the missing person, as deduced from her relatives. Therefore, an initial conclusion that would be provided to the police is that the body cannot be excluded as being that of the missing woman.

Table 2: Deduction of the genotype of the missing woman

Locus	Family of missing woman				Missing woman's possible geno-types*	Body
	Husband	Child 1	Child 2	Mother
	H	X	Y	M	U*	B
D3S1358	15,18	16,18	15,17	15,17	16,17	16,17
VWA	14...