The CACNA1A gene belongs to a family of genes that provide instructions for making calcium channels. These channels, which transport positively charged calcium atoms (calcium ions) across cell membranes, play a key role in a cell's ability to generate and transmit electrical signals. Calcium ions are involved in many different cellular functions, including cell-to-cell communication, the tensing of muscle fibers (muscle contraction), and the regulation of certain genes.
The CACNA1A gene provides instructions for making one part (the alpha-1 subunit) of a calcium channel called CaV2.1. This subunit forms the hole (pore) through which calcium ions can flow. CaV2.1 channels play an essential role in communication between nerve cells (neurons) in the brain. These channels help control the release of neurotransmitters, which are chemicals that relay signals from one neuron to another. Researchers believe that CaV2.1 channels are also involved in the survival of neurons and the ability of these cells to change and adapt over time (plasticity).
Source: https://ghr.nlm.nih.gov/gene/CACNA1A#
The CACNA1A spectrum is very broad. The following conditions are well documented in the literature.
Familial Hemiplegic Migraine 1
Episodic Ataxia 2
Spinocerebellar Ataxia 6
Paroxysmal tonic upward gaze
Epilepsy
Intellectual Disability
Autism
Source: Ingo Helbig http://epilepsygenetics.net/2015/09/11/cacna1a-this-is-what-you-need-to-know-in-2015/
Dystonia
Hypotonia
Dyskinesia
Mitochondrial Dysfuntion
Cortical Vision Impairment
ADHD/ADD
Trach and Tube Feeding Dependence
Dysmorphic Features
Increased Susceptibility to Brain Injury