Harlequin ichthyosis is very rare; its exact incidence is unknown.
How many people are affected by harlequin ichthyosis ?
<s>[INST] Answer the question truthfully, you are a medical professional. This is the question: How many people are affected by harlequin ichthyosis ? [/INST] \n Harlequin ichthyosis is very rare; its exact incidence is unknown.</s>