Newborn Screening for Severe Combined Immunodeficiency Using the Multiple of the Median Values of T-Cell Receptor Excision Circles

Michael F Cogley; Amy E Wiberley-Bradford; Sean T Mochal; Sandra J Dawe; Zachary D Piro; Mei W Baker

doi:10.3390/ijns7030043

Newborn Screening for Severe Combined Immunodeficiency Using the Multiple of the Median Values of T-Cell Receptor Excision Circles

Int J Neonatal Screen. 2021 Jul 12;7(3):43. doi: 10.3390/ijns7030043.

Authors

Michael F Cogley¹, Amy E Wiberley-Bradford¹, Sean T Mochal¹, Sandra J Dawe², Zachary D Piro¹, Mei W Baker^{1

3

4}

Affiliations

¹ Newborn Screening Laboratory, Wisconsin State Laboratory of Hygiene, University of Wisconsin School of Medicine and Public Health, Madison, WI 53726, USA.
² Office of Information Systems, Wisconsin State Laboratory of Hygiene, University of Wisconsin School of Medicine and Public Health, Madison, WI 53726, USA.
³ Genetics and Metabolism Division, Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Madison, WI 53726, USA.
⁴ Center for Human Genomics and Precision Medicine, University of Wisconsin School of Medicine and Public Health, Madison, WI 53726, USA.

Abstract

All newborn screening programs screen for severe combined immunodeficiency by measurement of T-cell receptor excision circles (TRECs). Herein, we report our experience of reporting TREC assay results as multiple of the median (MoM) rather than using conventional copy numbers. This modification simplifies the assay by eliminating the need for standards with known TREC copy numbers. Furthermore, since MoM is a measure of how far an individual test result deviates from the median, it allows normalization of TREC assay data from different laboratories, so that individual test results can be compared regardless of the particular method, assay, or reagents used.

Keywords: T-cell receptor excision circles; multiple of the median; newborn screening; severe combined immunodeficiency.