Table of contents
LinksIn search of the disappeared children
Asociación Pro-Búsqueda de niñas y niños desaparecidos
Physicians for Human Rights, 1994 press release
Physicians for Human Rights, 1995 press release
Chromosomal Labs, Inc
Forensic mathematics home page
Comments and inquiries are welcome (see home page for email)
Niñas y niños (possible adoptees) interested in finding their biological families I suggest you contact Rachel Shigikane, Human Rights Center UC Berkeley, phone 1-510-643-2713. rshig (at sign) berkeley (dot) edu
|has very generously agreed to perform DNA typing pro bono.|
I volunteered to assist, feeling that the problems of matching children with their relatives is very similar to the problem of identifying mass disaster victims. I've participated in or advised many related projects and developed various kinds of software especially as part of the World Trade Center identification project which I believe will be helpful with the family associations in El Salvador.
Update July 2006 visit to San SalvadorFour days in San Salvador gave me a chance to meet the dedicated staff of ProBusqueda and to learn a lot more about the history the nature of the civil war that caused the desaparecidos the technical and political difficulties and process involved in finding and reuniting children families, and the process of human rights work.
Our contingent included Physicians for Human Rights, Human Rights Center (UC Berkeley), and DNA folks.
14,000 missing children?
Among other things, data given to me extrapolates that the total number of children adopted out of the country in the 80's may be about 14,000.
These software facilities are
We tentatively assume that three factors will help narrow the search:
We've also decided, as a working criterion, to aim for 99.9% probability for each identification. Since
Posterior odds = (likelihood ratio)(prior odds),99.9% is posterior odds of 1000, and the prior odds are about 1/10 (easier to deal with than 1/9), this means that we need roughly
likelihood ratio > 10,000.
The workers in El Salvador are in the process of locating the biological relatives. Sometimes extra relatives are available but hard to get to. We would like to give them guidelines as to what combination of relatives is likely to be adequate.
The simulation procedure is to
The chart below summarizes the results for the various combinations of relatives that we have considered.
|Family references||Probability of identity
(Mean posterior probability at 10% prior)
|one full sibling||92.1%|
|sibling and aunt||94.4%||or sibling and uncle|
|sibling and two sister aunts||97.8%||i.e. the aunts or uncles are either both maternal or both paternal|
|sibling, aunt, uncle different sides||99.8%||e.g. maternal aunt, paternal uncle|
|sibling and half sibling||98%|
|sibling and two half siblings||99.4%||all children share mother; half-siblings share father with one another|
|one parent||99.9%||ignoring mutation|
|sibling and parent||99.996%|
|father and one half sibling||99.95%||maternal half-sibling|
|father and two half siblings||99.996%||maternal half-siblings of course|
|father and aunt||99.993%||maternal aunt (else why bother)|
|four grandparents||99.99%||surprise big bonus for all four|
|three grandparents and sibling||99.994%|