Document Type

Article

Publication Date

2-15-2022

Publication Title

Cell Rep Med

Keywords

JMG

JAX Source

Cell Rep Med 2022 Feb 15; 3(1):100501

Volume

3

Issue

2

First Page

100501

Last Page

100501

ISSN

2666-3791

PMID

35243414

DOI

https://doi.org/10.1016/j.xcrm.2021.100501

Abstract

Analysis of large-scale human genomic data has yielded unexplained mutations known to cause severe disease in healthy individuals. Here, we report the unexpected recovery of a rare dominant lethal mutation in TPM1, a sarcomeric actin-binding protein, in eight individuals with large atrial septal defect (ASD) in a five-generation pedigree. Mice with Tpm1 mutation exhibit early embryonic lethality with disrupted myofibril assembly and no heartbeat. However, patient-induced pluripotent-stem-cell-derived cardiomyocytes show normal beating with mild myofilament defect, indicating disease suppression. A variant in TLN2, another myofilament actin-binding protein, is identified as a candidate suppressor. Mouse CRISPR knock-in (KI) of both the TLN2 and TPM1 variants rescues heart beating, with near-term fetuses exhibiting large ASD. Thus, the role of TPM1 in ASD pathogenesis unfolds with suppression of its embryonic lethality by protective TLN2 variant. These findings provide evidence that genetic resiliency can arise with genetic suppression of a deleterious mutation.

Comments

This is an open access article under the CC BY-NC-ND license.

Share

COinS