Dyskinesia is an umbrella term encompassing a range of different movements. These are all movements that can be out of your control. Dyskinesia is very common in cerebral palsy.
Oropharyngeal dysphagia, or OPD, is an impairment of the oral or pharyngeal phases of the swallow. This can impair muscle movements and coordination of the mouth, such as the lips, tongue, jaw, cheeks, palate, and also muscles of the pharynx and the entry to the airway.
To give you an idea about genetic variation between each of us, there are about three million differences in our genetic code. They go to influence the color of our hair and the color of our eyes, the way we walk.