Neonatal Bartter syndrome diagnosed by rapid genomics following low risk pre-conception carrier screening

Advances in the speed and accessibility of genomic sequencing are broadening the application of this technology to rapid, acute care diagnostics and pre-conception carrier screening. In both circumstances, genetic counselling plays a critical role in preparing couples for the strengths and limitations of the testing. For pre-conception carrier screening in particular, it is important that parents and clinicians are aware that even in the absence of an identified risk for recessive disease, a baby with a genetic condition may still be conceived. As an example, we present the genomic journey of a couple who underwent pre-conception carrier screening and following a low-risk result, delivered a baby boy who was diagnosed with Type 1 Bartter syndrome. Ultra-rapid, post-natal, trio whole genome sequencing resolved both parents as carriers of pathogenic variants in SLC12A1, a gene not included in the original pre-conception screening panel. This family's story highlights (i) the intricacy of gene selection for pre-conception screening panels, (ii) the benefits of high-quality pre-test genetic counselling in supporting families through adverse genomic findings and (iii) the role rapid genomics can play in resolving uncertainty for families and clinicians in circumstances where suspicion of genetic disease exists. This article is accompanied by a Patient Voice perspective written by the child's parents, placing emphasis on the essential role genetic counselling played in their journey.