Este artigo descreve pela primeira vez diagnóstico genético pré-implantacional (DGPI, PGD em inglês) com fertilização in-vitro em pacientes com acondroplasia e discute também as considerações e dificuldades éticas e obstétricas que tem de ser tidas em conta.
Embora o estudo tenha sido feito com um número reduzido de casais (apenas 3), um aspeto importante mencionado no artigo é que os autores encontraram dificuldades na estimulação dos ovários e na colheita dos oócitos das mulheres com acondroplasia que participaram no estudo, resultando numa ausência de gravidezes usando este método. Uma das dificuldades apresentadas tem que ver com a posição dos ovários nas mulheres com acondroplasia, visto que se encontram muito altos na região pélvica.
Moutou, C. (2003). Preimplantation genetic diagnosis for achondroplasia: genetics and gynaecological limits and difficulties. Human Reproduction, 18(3), 509-514. doi:10.1093/humrep/deg123
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Abstract
"BACKGROUND: We report the ®rst attempts at preimplantation genetic diagnosis (PGD) and IVF and their accompanying dif®culties for achondroplasia (ACH) patients.
METHODS: A PGD test was developed using fluorescent single cell PCR on lymphoblasts from patients and controls and from blastomeres from surplus IVF embryos. A specific digestion control based on the use of two fluorochromes was elaborated. Ovarian stimulation and oocyte retrieval were carried out using conventional protocols.
RESULTS: We performed 88 single cell tests for which amplification was obtained in 86 (97.7%) single lymphoblasts. Allele drop out (ADO) was observed in two out of 53 (3.7%) heterozygous lymphoblasts. If we combine the results from the blastomere testing from surplus embryos with those from PGD cycles and re-analysis after PGD, we obtained a PCR signal in 84% of cases of which 91% were correctly diagnosed at the G380 locus. A total of six cycles were performed resulting in three embryo transfers. We observed dificulties in ovarian stimulation and oocyte retrieval with affected female patients. No pregnancy was obtained.
CONCLUSION: A PGD test for ACH is now available at our centre but our initial practice raises questions on the feasibility of such a test, specially with affected female patients."