I know that congenital insensitivity to pain exists and is autosomal recessive. There is a village in Sweden where 40 cases of this rare genetic disease were reported.
I am writing a story with a strange genetic disease called congenital insensitivity to itch. In my story, congenital insensitivity to itch is common in a village inhabited by 600 humans: 30 of them have it.
So, I wonder if my genetic disease is possible or a total fiction. What would be congenital insensitivity to itch's mode of inheritance: autosomal dominant (like Marfan syndrome), autosomal recessive (like cartilage-hair hypoplasia), X-linked dominant (like X-linked pituitary gigantism), or X-linked recessive (like Hunter syndrome)?
If this is autosomal, what chromosome is linked? Chromosome 1 (like Hutchinson-Guilford progeria), chromosome 2 (like Ehlers-Danlos syndrome), chromosome 3 (like retinitis pigmentosa), chromosome 4 (like achondroplasia), chromosome 5 (like Sotos syndrome), chromosome 6 (like hemochromatosis), chromosome 7 (like tritanopia), chromosome 8 (like Werner syndrome), chromosome 9 (like cartilage-hair hypoplasia), chromosome 10 (like type 2 multiple endocrine hyperplasia), chromosome 11 (like sickle-cell anaemia), chromosome 12 (like phenylketonuria), chromosome 13 (like Wilson disease), chromosome 14 (like Krabbe disease), chromosome 15 (like Marfan syndrome), chromosome 16 (like Morquio syndrome), chromosome 17 (like type 1 neurofibromatosis), chromosome 18 (like type-C Niemann-Pick disease), chromosome 19 (like Donohue syndrome), chromosome 20 (like adenosine deaminase deficiency), chromosome 21 (like autoimmune polyendrocrinopathy-candidiasis-ectodermal-dystrophy), or chromosome 22 (like type 2 neurofibromatosis)?
I know I made an extremely long enumeration because the vast majority of the human genome is nuclear and autosomal, sorry.