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We have recently cloned the gene for X-linked hypophosphataemic rickets (HYP; HYP consortium, Nature genetics PEX gene). I am now actively devising experiments at elucidating gene function. I write to ask whether there are clinicians/investigators who have patients with oncogenic hypophosphataemic osteomalacia (OHO), or related phosphaturic factor releasing tumours (Linear sebaceous naevus syndrome, fibrous dysplasia of bone, neurofibromatosis, oat cell carcinoma). These tumours are very rare, and may well provide the key to unravelling the putative substrate activated on by PEX. They tend to be haemangiopericytomas of mesenchymal origin, and produce factor(s) resulting in a renal phosphate leak, and inappropriate depression of 1,25 Vit levels, osteomalacia and consequent hypophospahtaemia.

I would be most interested in:

1.Tumour tissue. 2. blood before and after removal of tumour.

In addition any blood/DNA samples from patients with familial X-linked rickets would also be appreciated.

X-linked (Xp) Spondyloepiphyseal dyspalsia tarda (SEDL):

I am also collecting families with SEDL, with the ultimate aim of mapping and cloning this gene (just distal to HYP). Blood and /or DNA from such families would be most welcome.

Thank you for your help.