Keratinization

Question 1

1) Which bovine inherited congenital disease is similar to human harlequin ichthyosis where there are alopecic areas on the muzzle, eyelids and ears, and the body is covered by thick, dark-gray, dry scale-like hyperkeratotic material resulting in early neonatal death and what is the mode of inheritance?
a. Ichthyosis congenital + simple autosomal dominant gene
b. Ichthyosis fetalis (bovine harlequin foetus) + simple autosomal recessive gene
c. Epitheliogenesis Imperfecta + simple autosomal recessive gene
d. Lamellar ichthyosis + simple autosomal dominant gene

Answer 1

Ichthyosis fetalis (bovine harlequin foetus) 
Simple autosomal recessive gene

Question 2

Name the keratin that is expressed in each layer of the epidermis.

Answer 2

Stratum Basale - K5/K14. Low levels K15

Stratum Spinosum - K1/K10. K6/K16 in psorasis. Lamellar granules present. Metabolic barrier.

Stratum Granulosum- K1/K2 keratohyalin granules present. First layer that begins to form the cornified envelope

Stratum Lucidum- present in footpads and nasal planum. Contains eleidin

Stratum Corneum- There are no phospholipids in the cell membrane of corneocytes so it is not a “true” cell membrane