Análisis de paternidad utilizando cuatro marcadores de DNA amplificados mediante la reacción en cadena de polimerasa / Paternity analysis using 4 DNA markers amplified by polymerase chain reaction

Background: DNA typing in forensic analysis is a useful tool to analyze paternity due to its high discrimination power. Aim: To report the experience of Servicio Medico Legal in Santiago, resolving cases of dubious paternity. Subjects and methods: Four highly polymorphic loci, amplified by polymerase chain reactions, were analyzed in 153 cases of uncertain paternity. The paternity index was calculated for each case. Results: The four genetic markers analyzed provided an exclusion probability of 0.933 for the general population in Santiago. Thirty seven cases were excluded as parents. In 31 cases, the paternity index ranged from 19 to 100, considered as probable paternity and 77 cases had an index of over 100, considered as almost certain paternity. Eight cases had an index between 0.5 and 19, considered as inconclusive. All loci met Hardy-Weinberg expectations and their frequencies were similar to other data from people living in Santiago. Conclusions: The use of these genetic markers proved to be very useful, reliable and with a high exclusion power for paternity analysis

Análisis de paternidad en casos de incesto, utilizando polimorfismo del ADN de loci multialélicos / Paternity analysis in incest cases using DNA polymorphisms of multiallelic loci

The analysis of genetic markers in man allows to efficiently resolve cases of dubious paternity. Lately, the use of genetic markers derived from DNA analysis allows high exclusion probabilities. A particular case are those consultations whom the progenitors are closely related, in which the criteria to attribute paternity are modified. The present report explains the analysis methods and interpretation of results in situations of doubtful paternity in cases of incest between father and daughter, using monolocus DNA polymorphisms. The method is illustrated through the analysis of 4 cases seen at the Servicio Médico Legal of Santiago. To be able to determine paternity in these cases of incest, at least three multiallelic loci in which mother and son have different genotypes must be examined