This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Autoimmune skin disorders, Subject name: Dental
Steroid suphatase deficiency is seen in 
Select and explain. 
A. Ichthyosis vulgaris, B. Lamellar Ichthyosis, C. 'X' linked recessive icthyosis, D. None of the above
C: 'X' linked recessive icthyosis
Answer: C: 'X' linked recessive icthyosis 
Explanation: X-linked ichthyosis (abbreted XLI) is a skin condition caused by the hereditary deficiency of the steroid sulfatase (STS) enzyme that affects 1 in 2000 to 1 in 6000 males. XLI manifests with dry, scaly skin and is due to deletions or mutations in the STS gene. Ref Harrison20th edition pg 1332