see there is a problem with ure question..
firstly with osteoporosis.. its low bone mass density (specifically SD -2.5 or less).. otherwise its osteopenia
and its a tendency.. not the disease.. tat is heriditary
cos they have 3 causes..
1)low gonadal hormones (e.g oestrogen),
2)poor bone formation and renal function with age,
3)Other hormonal like PTH defiencies.. or excessive levels of glucorticoids
so its realli if u had family with oestrogen secretion problems.. when u could get osteoporosis.. but then u get other things too ?! if u want similar.. then u can use Gauchers disease..
with Diabetes ..
melitus type 1.. its the destruction of beta cells in the pancreas... islet of langerhans resulting in low insulin ..
its an autoimmune condition..with twins there is a link.. and certain alleles of the HLA its recessive
http://www.d4pro.com/IDM/site/type_1_diabetes_and_ms_the_key.htm
these HLA are the receptors tat present all proteins to the immune system from cells.. the immune system in certain alleles then to cause activation of auto immune.. its multi factorial but there is a link.. mabbe consider using haemophilia A or B for a clearer heriditary disease
there is a diabetes insipidus tat IS hereditary
"Hereditary Hypothalamic Diabetes Insipidus" is rare... and hard to find.. well for me it was a bitch.. .
certain groups have quite a few hereditary diseases lik tay-sachs amongst the Ashkenazi Jewish population.. they hav other well known hereditary diseases due to intermarriage..
hope tat helps