PGD by FISH for a Reciprocal Translocation: First Baby from India

Abstract

A couple with a history of five early miscarriages due to a balanced reciprocal translocation t(6;19) (p22;q13.4) in the wife, was referred for preimplantation genetic diagnosis (PGD) by fluorescence in situ hybridization (FISH). After oocyte retrieval, nine embryos were obtained. One cell from each embryo was biopsied, fixed and subjected to FISH using centromere and subtelomere probes for chromosomes 6 and 19. Five embryos which had unbalanced translocations, were not transferred. A balanced translocation or absence of translocation was seen in three embryos, which were transferred. One embryo had an anucleate cell and subsequently arrested. A pregnancy was achieved in the first intracytoplasmic sperm injection cycle itself and resulted in the birth of a healthy baby. This is the first baby after PGD for a reciprocal translocation in India. In 2010, the team of the authors reported the first successful pregnancy after PGD for a Robertsonian translocation and a normal child was born.

Immune alterations in recurrent implantation failure

“…Testing for Aneuploidies (PGT-A) can be used to improve outcomes of ART. [14][15][16] Considering that nearly 40-60% of preimplantation embryos harbor chromosome aneuploidies, 17 PGT-A was advocated for couples with normal karyotype but having RIF. The hypothesis was that these patients had higher proportions of genetically abnormal embryos and screening them out would improve pregnancy rates.…”

“…The resultant embryos using gametes from such couples can have unbalanced translocation and these may not be viable resulting in an implantation failure. In such couples, Preimplantation Genetic Testing for Aneuploidies (PGT‐A) can be used to improve outcomes of ART 14–16 . Considering that nearly 40–60% of preimplantation embryos harbor chromosome aneuploidies, 17 PGT‐A was advocated for couples with normal karyotype but having RIF.…”

Preimplantation genetic testing: Its evolution, where are we today?

“…[58596061] With PGT-A by FISH, our clinical pregnancy rate was 36% per patient and 28% per cycle. Our team reported the first live births in India for a Robertsonian[62] and reciprocal translocation,[63] inversion with a cryptic translocation picked up on pre-PGT-A workup[64] and pregnancy after PGT for a complex translocation. [65] Currently, we use the NGS platform to offer PGT-A.…”

Preimplantation Genetic Diagnosis in India: The Current Scenario and Potential Developments

“…Pre-PGD work-up can involve HLA typing which is used to find a matching donor in cases of blood disorders like hemoglobinopathies, aplastic anaemia, leukaemia, hemochromatosis etc. [7,21,22].…”

“…Studies show that PGT has reduced the rate of translocation related pregnancy loss from [ 90 to * 15%. Another report stated the first successful pregnancy and birth of a normal child after PGT for a reciprocal translocation in India in 2014 [21,26,30].…”