Hi and welcome,
'scattered Foci of Flair noted in Periventrical + subcortal white matter' doesn't really say anything, these types of findings are very very common non specific MRI results, 'periventrical' basically means next to or around the ventricle, periventricular white matter changes are not associated with any particular symptoms. 'Subcortical basically means the white matter below the cortex which is the top, main section and grey matter of the brain........honestly without any other more specific information in your report foci in those location are more likely to be silent micro vascular related and less likely to be related to be demyelinating lesions like the type of lesions suggestive-consistent with a neurological condition like MS.
eg "The periventricular lesions suggestive of MS are often ovoid and aligned perpendicular to the long axis of the ventricles. This pattern is the result of the alignment of the lesions along the perivenular spaces. Additional characteristic features include lesions along the callosal septal interface, as well as lesions that are confluent in nature and greater than 6 mm in diameter with a periventricular location."
https://radiologykey.com/white-matter-and-neurodegenerative-diseases/
Technically MS is not suppose to be a genetically inheritable medical condition, at best with neurological conditions like MS there's a 'genetic susceptibility' but it's more the norm for pwMS to be the only person in their family to be dx than for there to be multiple family members dx with MS, sometimes MS can run in families but as i said it's not common.
I would expect your brain MRI 'may not' be yielding enough information if that's all it say's, there's not enough to be suggestive of your problems being caused by neurological damage of some kind. If you haven't had a spinal MRI, visual testing eg VEP or any cognitive assessment etc done as yet, you've probably got a lot more tests to go through before you'll get a better idea of what type of medical condition it could be..
Hope that helps......JJ