Multiplex and multimodal mapping of variant effects in secreted proteins via MultiSTEP.

ABSTRACT: Despite widespread advances in DNA sequencing, the functional consequences of most genetic variants remain poorly understood. Multiplexed assays of variant effect can measure the function of variants at scale but cannot readily be applied to the ~10% of human genes encoding secreted proteins. Here we develop a flexible, scalable human cell surface display method, multiplexed surface tethering of extracellular proteins (MultiSTEP), to study the consequences of missense variation in coagulation factor IX (FIX), a serine protease in which genetic variation can cause hemophilia B. We combine MultiSTEP with a panel of antibodies to detect FIX secretion and post-translational modification (PTM), measuring 44,816 variant effects for 436 synonymous variants and 8,528 of the 8,759 possible F9 misse

SUBMITTER: Popp NA 

PROVIDER: S-EPMC12373428 | biostudies-literature | 2025 Oct

REPOSITORIES: biostudies-literature