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Updated: Jun 9, 2026

Isolation of Primary Patient-specific Aortic Smooth Muscle Cells and Semiquantitative Real-time Contraction Measurements In Vitro
Published on: February 15, 2022
De novo ACTA2 mutation causes a novel syndrome of multisystemic smooth muscle dysfunction
Dianna M Milewicz1, John R Østergaard, Leena M Ala-Kokko
1Department of Internal Medicine, University of Texas Health Science Center at Houston, Houston, Texas 77030, USA. dianna.m.miledwicz@uth.tmc.edu
Abstract:
Smooth muscle cells (SMCs) contract to perform many physiological functions, including regulation of blood flow and pressure in arteries, contraction of the pupils, peristalsis of the gut, and voiding of the bladder. SMC lineage in these organs is characterized by cellular expression of the SMC isoform of α-actin, encoded by the ACTA2 gene. We report here on a unique and de novo mutation in ACTA2, R179H, that causes a syndrome characterized by dysfunction of SMCs throughout the body, leading to aortic and cerebrovascular disease, fixed dilated pupils, hypotonic bladder, malrotation, and hypoperistalsis of the gut and pulmonary hypertension.
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