PREIMPLANTATION GENETIC DIAGNOSIS FOR HUNTINGTON’S DISEASE - CASE REPORT AND LITERATURE REVIEW

Abstract

Background: Huntington’s disease is a rare, neurodegenerative, autosomal dominant disorder with adult onset caused by an expansion of 36 or more CAG trinucleotide repeats in the HTT gene. In Brazil and in some other countries, carriers of HTT’s expanded allele of submitted to in vitro fertilization procedure can investigate embryos genetically to identify the ones that have inherited the expanded allele and the ones that inherited only the normal size alleles. In some instances, an individual has a positive familial history for the disease and do not want to know his/her personal carrier status but is willing to conceive children without the disease. Objective: to demonstrate the reproductive possibilities available to patients with Huntington disease through a case report and literature review. Methods: Here, we discussed the application and viability of the genetic screening techniques, based on a non-disclosure case of Preimplantation Genetic Testing (PGT). Results: a couple submitted to a non-disclosure test for Huntington disease was submitted to IVF, embryo biopsy and genetic analysis of the samples due to a familial history of the condition. Chromosome and mutation specific tests were applied, and one embryo was selected for uterine transfer. The couple was not informed why the other embryos were discharged. Conclusion: Although many ethical and practical aspects are involved in this decision, a non-disclosure PGT can be offered as an option for these couples, besides sperm, egg or embryo adoption, or child adoption.