Harlequin skin change is seen due to mutation of which gene?
Ans. is 'a' i.e., ABCA 12 Harlequin Ichthyosis* Harlequin ichthyosis (HI) is caused by mutations in the ABCA 12 gene.* Mutation in the gene leads to defective lipid transport and ABCA 12 activity is required for the generation of long- chain ceramides that are essential for the development of the normal skin barrier. It is inherited by autosomal recessive mode of inheritance.Clinical Manifestations* At birth, markedly thickened, ridged, and cracked skin forms horny plates over the entire body, disfiguring the facial features and constricting the digits.Treatment* Initial treatment includes high fluid intake to avoid dehydration from transepidermal water loss and use of a humidified heated incubator, emulsifying ointments, careful attention to hygiene, and oral retinoids (1 mg/kg/ day).* Prenatal diagnosis has been accomplished by fetoscopy, fetal skin biopsy, and microscopic examination of cells from amniotic fluid.Extra edge* N.B. The fetus in ichthyosis appears grostesque and the appearance is called harlequin fetus. But, it is different from Harlequin color change.Harlequin color change* This rare but dramatic vascular event occurs in immediate newborn period and is most common in low birth weight infants.* If reflects an imbalance in the autonomic vascular regulatory mechanism.* When the infant is placed on the side, the body is bisected longitudinally into pale upper half and a deep red dependent half.
ABC A 12
FAD
Keratin 1
ALOXE 3
Genetics And Genetic Disorders