For example GDF6 gene plays an important role in bone development and joint formation. The mutation in these genes can result in Klippel-Feil syndrome. As a result of having congenital Klippel-Feil syndrome, the spinal anatomy of the individual will present abnormal fusion of any two of the seven cervical bones in the neck. This is considered to be an anomaly of cervical bones. It affects the functioning of cervical spinal nerves (C1 - C8) because of compression on the spinal cord. Spinal stenosis also adds damage to the spinal cord resulting in symptoms that are caused by cervicocranial syndrome. Trauma
Traumatic injuries are caused when external forces damage the cervical spine, giving rise to various symptoms. In a motor vehicle accident, the vehicle jerks the neck forward and backward resulting in cervical spine damage. This is called whiplash. The neurological and biological symptoms resulting from neck trauma emerge as a culmination of clinically isolated or combined symptoms caused by cervicocranial syndrome. Pathophysiology
The body is innervated by spinal nerves that branch off from the spinal cord. This innervation enables the brain to receive sensory inputs and send motor outputs. There are 8 cervical spinal nerves of the peripheral nervous system. Cervical spinal nerves C1, C2 and C3 help control the movements of the head and neck. Cervical spinal nerve C4 helps control upward shoulder movements. Cervical spinal nerve C3, C4 and C5 help power the diaphragm and aid in breathing. Cervical spinal nerve C6 helps in wrist extension and some functioning of biceps.
Cervicocranial syndrome or (Craniocervical Junction Syndrome: CCJ syndrome) is a neurological illness. It is a combination of symptoms that are caused by an abnormality in the neck. The bones of the neck that are affected are cervical vertebrae (C1 - C7). This syndrome can be identified by confirming cervical bone shifts, collapsed cervical bones or misalignment of the cervical bone leading to improper functioning of cervical spinal nerves. [1]  Cervicocranial syndrome is either congenital or acquired (as a result of injury or disease). Some examples of diseases that could result in cervicocranial syndrome are Chiari disease, Klippel-Feil malformation osteoarthritis, and trauma. Treatment options include neck braces, pain medication and surgery. The quality of life for individuals suffering from CCJ syndrome can improve through surgery. Signs and Symptoms
Cervicocranial syndrome has a wide range of symptoms. These symptoms often include:

Vertigo
Chronic Headache aka Cephalea
Tinnitus
Facial Pain
Ear Pain
Dysphagia
Carotidynia
Neck Pain (ex: during movement such extension and flexion)
Syncope
Sinus congestion
Neck Crepitus Sound
Loss of vision
Involuntary eye-movement
Severe Fatigue
Chest Pain
Brain Fog

Cause
The cause of cervicocranial syndrome is either due to a defect (genetic mutation or development of diseases later in life) or an injury pertaining to the neck: cervical area, that damages the spinal nerves traveling through the cervical region resulting in ventral subluxation. Examples of cases that can result in cervicocranial syndrome are: car accidents, trauma, osteoarthritis, tumor, degenerative pathology and other numerous causes of vertebral instability. There is no single cause that can mainly cause cervicocranial syndrome. Genetic
The genes GDF6, GDF3, MEOX1 used as examples, encode for making proteins that help with development.