Dear Colleague,

The last, 13th International PGD conference, held in Canterbury, April 30 - May 2, 2014 (see PGDIS website www.pgdis.org), was devoted to the scientific aspects of PGD and the analysis of the emerging new technologies for testing oocytes and embryo, including next generation sequencing (NGS) and Karyomapping. The first validation data of these new molecular diagnostics, and the advantages and disadvantages of their wider clinical application were addressed, as a possible tool for improving reproductive outcome of ART.

With a recent rapid shift from the cleavage stage to blastocyst biopsy, coupled with vitrification/ frozen transfer, and microarray or NGS based 24-chromosome aneuploidy testing, an increasing body of data became available, suggesting an improving impact of PGD on reproductive outcome, particularly in poor prognosis ART patients, which was not consistently evident with previous cleavage stage aneuploidy testing.

The considerable progress in NGS, particularly for preimplantation 24-chromosome aneuploidy testing, may in the future provide the basis for a comprehensive PGD for both single gene and chromosomal disorders in one test with a single biopsy material. However, currently the technique still has significant technical limitations in detecting ADO, testing for dynamic mutations and avoiding misdiagnosis due to pseudogenes. Some of these limitations can be overcome by Karyomapping, although there are a number of other important limitations, that Karyomapping is of limited potential if for some reason both parents are not available, if both parents have identical recessive mutations in a highly consanguineous background, or if affected children are recombinant or have a de novo mutation.

On the other hand, it was demonstrated that combined testing for single gene using the traditional approach as well as chromosomal disorders using arrays or NGS may reliably be performed, with WGA or MDA product obtained at the first step of microarray-based 24-chromosome aneuploidy testing. This has presently been demonstrated for a few hundreds of PGD patients of advanced reproductive age and shows an extremely high accuracy.

The progress in improving of the above technologies will be further explored by the 14th International PGD Conference, to be held in Chicago, May 11- 13 May, 2015, which will be devoted to 25th Anniversary of PGD. However, the main emphasis of this Conference will be on the clinical aspects of PGD in relation to the development and applications of NGS and other new molecular techniques for comprehensive PGD of monogenic and chromosomal disorders. To further support the current shift and growing demand for blastocyst biopsy, the Pre-Congress Hands-on Workshop on the procedure, combined with novel methods for genetic testing, will be organized for the seventh time in Istanbul, May 7-9, 2015 (see www.pgdis.org ). The Chicago Conference venue will be Museum of Contemporary Art, with the HQ’s Hotel - Ritz Carlton, both in the city of Chicago.

The progress in the organization of the Conference may be followed through the PGDIS website (www.pgdis.org), or Vega Travel International (www.vegatravel.net) - the organizing secretariat of the PGDIS Chicago Conference, May 11-13, 2015.

Sincerely,