A8V is point mutation on

Troponin C Troponin C is a protein which is part of the troponin complex. It contains four calcium-binding EF hands, although different isoforms may have fewer than four functional calcium-binding subdomains. It is a component of thin filaments, along ...

(cTNC) that leads to a

hypertrophic cardiomyopathy Hypertrophic cardiomyopathy (HCM, or HOCM when obstructive) is a condition in which muscle tissues of the heart become thickened without an obvious cause. The parts of the heart most commonly affected are the interventricular septum and the ...

. The coordinated cardiac muscle contraction is regulated by the troponin complex on thin filament (troponin C which is calcium binding,

troponin T Troponin T (shortened TnT or TropT) is a part of the troponin complex, which are proteins integral to the contraction of skeletal and heart muscles. They are expressed in skeletal and cardiac myocytes. Troponin T binds to tropomyosin and help ...

that plays the role with

tropomyosin Tropomyosin is a two-stranded alpha-helical, coiled coil protein found in many animal and fungal cells. In animals, it is an important component of the muscular system which works in conjunction with troponin to regulate muscle contraction. It ...

, and

troponin I Troponin I is a cardiac and skeletal muscle protein family. It is a part of the troponin protein complex, where it binds to actin in thin myofilaments to hold the actin-tropomyosin complex in place. Troponin I prevents myosin from binding to act ...

which has an inhibitory action annulating the S1 ATPase activity in the presence of tropomyosin and troponin and absence of Ca²⁺). This mutation is determined by the change of Alanine to Valine at nucleotide 23 from C to T. Patients with this type of mutation shows thickness on the left ventricle wall of around 18 mm, compared to the normal this thickness would be 12 mm.{{Cite journal, last1=Pinto, first1=Jose Renato, last2=Parvatiyar, first2=Michelle S., last3=Jones, first3=Michelle A., last4=Liang, first4=Jingsheng, last5=Ackerman, first5=Michael J., last6=Potter, first6=James D., date=2009-07-10, title=A Functional and Structural Study of Troponin C Mutations Related to Hypertrophic Cardiomyopathy, journal=Journal of Biological Chemistry, volume=284, issue=28, pages=19090–19100, doi=10.1074/jbc.M109.007021, issn=0021-9258, pmc=2707221, pmid=19439414, doi-access=free Also, A8V affects the Ca²⁺ binding affinity compared to normal genotype and increased sensitivity on force development.

References

Mutation Troponin