Deafness knows no skin color, civilization, or family. Deafness happens in all parts of the globe where the widely used language is vastly different from another region/country.
Yes, deafness has shared struggles, shared language, shared behaviors, and shared views on the hearing.
The difference is that in no matter what part of the globe a deaf person lives, they will generally follow the societal norms for their civilization.
For example; a deaf mother in India is likely to dress similarly to the other women, eat the same food, and likely have the same religious belief she was raised with as a child such as Hindu. She will be able to read and write Hindu scripts.
A deaf man in the United States is likely to dress similarly to the other men, eat similar food, and again likely have the same religious belief he was raised with as a child such as Christianity. He will be able to read and write English.
Culturally these two couldn't be more different but they share the same struggles in dealing with the hearing and likely will share a common sign language (if ASL is taught in India to the deaf.) They will also have the same feelings about hearing people who are inconsiderate of the deaf as well as hearing people who are genuinely trying to help the deaf. They will both have shared behaviors when interacting with their local deaf community such as tapping the floor to get someone's attention and using visual cues in their surroundings to help them be more aware.
As much as I would like for the Deaf worldwide to receive recognition as not just as a disabled group of people but rather as a culture or society all in it's own right, I don't think we should receive 'ethnic' status as deafness encompasses ALL ethnic groups worldwide. Just my two cents on the subject.