On the question of perspectives of preconception screening of gamete donors in the era of expanded neonatal

Since January 2023 expanded neonatal screening (ENS) has been carried out in the Russian Federation, including the determination of TREC/KREС markers, which allow one to suspect primarily severe combined immunodeficiency (SCID) and agammaglobulinemia (AGG) before the development of severe infectious complications. Screening revealed a boy with a decrease in KREC to 0 copies/105 cells and a marked decrease in the number of B-lymphocytes. Whole exome sequencing revealed a hemizygous pathogenic variant in the BTK gene, which was previously described in patient with X-linked agammaglobulinemia, type 1. The child was born as a result of in vitro fertilization using donor oocyte. Given the development of genetic technologies, the introduction of preconception screening for gamete donors is a reasonable prospect which however requires further investigation.

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