Noninvasive prenatal paternity determination using microhaplotypes: a pilot study

Background The use of noninvasive techniques to determine paternity prenatally is increasing because it reduces the risks associated with invasive procedures. Current methods, based on SNPs, use the analysis of at least 148 markers, on average. Methods To reduce the number of regions, we used microhaplotypes, which are chromosomal segments smaller than 200 bp containing two or more SNPs. Our method employs massively parallel sequencing and analysis of microhaplotypes as genetic markers. We tested 20 microhaplotypes and ascertained that 19 obey Hardy–Weinberg equilibrium and are independent, and data from the 1000 Genomes Project were used for population frequency and simulations. Results We performed simulations of true and false paternity, using the 1000 Genomes Project data, to confirm if the microhaplotypes could be used as genetic markers. We observed that at least 13 microhaplotypes should be used to decrease the chances of false positives. Then, we applied the method in 31 trios, and it was able to correctly assign the fatherhood in cases where the alleged father was the real father, excluding the inconclusive results. We also cross evaluated the mother-plasma duos with the alleged fathers for false inclusions within our data, and we observed that the use of at least 15 microhaplotypes in real data also decreases the false inclusions. Conclusions In this work, we demonstrated that microhaplotypes can be used to determine prenatal paternity by using only 15 regions and with admixtures of DNA.

Presumption of the child’s origin from the husband of the mother within 300 days of marriage termination or annulment, and in the event of judicial separation – de lege lata and de lege ferenda remarks

The article is dedicated to the institution of the presumption of the child's origin from the husband of the mother as one of three ways to determine the child's origin from the father. In the opinion of the author, with the current availability of genetic tests (DNA), the regulation “extending” this presumption to children born after the termination or annulment of marriage, after the judicial separation and declaring any of the parents to be deceased, does not implement the principle of protecting the good of the child and in particular his right to grow up in the family and the identity right. The current shape of the regulation of the Family and Guardianship Code regarding this presumption significantly hinders, and certainly delays, the possibility of establishing biological paternity and granting the biological father the status of legal father, which is most desirable and justified. The current legal status is not favorable either for the child, his biological father or his mother's ex-husband. Taking into account the progress of genetics by the legislator and enabling the recognition of paternity on the basis of out-of-court DNA test results at any time of the child's birth after the termination or annulment of his mother's marriage by the genetic father, would significantly improve the paternity determination procedure and relieve the courts. These changes are also of great importance in the context of family evolution and the growing acceptance of informal relationships in which children are born and raise.

Use of DNA tests in cases of determining legal paternity

The objective of the study involves testing the influence of accessibility of DNA tests, on paternity determination. Without doubt, DNA tests determining the family relationship have become one of the most frequently performed genetic tests commercially. They are carried out both at individual request, as well as for use in judicial proceedings. Undoubtedly, the common use of DNA tests to exclude consanguinity has become very popular in judicial practice. Moreover, it seems that due to the fact that DNA tests are quite accurate in determining blood relations, the regulations of the Family and Guardianship Code have been changed in order to base paternity on the certainty of genetic relation. The study also involved the regulations of the Family and Guardianship Code as well as judicial decisions in order to indicate the nature of evidence from genetic testing and its impact on paternity recognition.

Applications of Cell-Free Fetal DNA in Maternal Serum

ABSTRACT Cell-free fetal DNA (cffDNA) is available in the maternal circulation throughout pregnancy and can be used for noninvasive prenatal diagnosis including, determination of fetal sex, identification of specific single gene disorders, typing of fetal blood groups (RhD), paternity determination and potentially routine use for Down's syndrome (DS) testing of all pregnancies. I searched published literature on the PubMed and databases on Scopus interface systematically using keyword's cffDNA, noninvasive diagnosis, fetal DNA in the maternal serum. Reference lists from the papers were also searched. cffDNA representing only 3% of the total cell-free circulating DNA in early and rising to 12% in late pregnancy, clinical investigations has already demonstrated the potential advantage, such as improving safety, earlier diagnosis and comparative ease of testing using cffDNA technology. The discovery of cffDNA circulating in the maternal serum has opened the door to noninvasive prenatal diagnosis testing with novel clinical implications. How to cite this article Ghorbian S. Applications of Cell-Free Fetal DNA in Maternal Serum. Int J Infertility Fetal Med 2012;3(2):33-39.

Paternity determination of interspecific rhododendron hybrids by genomic in situ hybridization (GISH)

Genomic in situ hybridization (GISH) has been proved to be the most effective and accurate technique for confirmation of hybrid character. The objective of our study was to adapt and optimize a GISH protocol for identification of donor chromatin in hybrids obtained by interspecific crosses between five Rhododendron taxa ( R. aureum , R. brachycarpum , R. catawbiense ‘Catharine van Tol’, R. catawbiense ‘Nova Zembla’, and R. yakushimanum ‘Koichiro Wada’). Positive results were obtained only when we used mitotic chromosome spreads prepared from anthers. The best differentiation of maternal and paternal chromosomes in hybrid genomes was obtained when 50 ng of probe was applied together with blocking DNA at a concentration of 3.0 µg/µL. The results demonstrate that GISH is a practical tool for detection of alien genomes and analysis of the constitution of the chromosomes in rhododendron hybrids.