Table 2: A summary of the types of mutations identified (from the literature review) for each subtype of ARCI (autosomal recessive congenital ichthyosis) and the corresponding effects on the ABCA12 protein. This table shows that the most deleterious changes often result in the HI phenotype, while the mutations which have a less severe effect on the protein often lead to the CIE and LI phenotypes.

Number of patientsPhenotypeMutations

42HI4.8% frameshift insertions
7.1% exonic deletions
9.5% in-frame deletions
9.5% missense
11.9% splice site
16.7% frameshift deletions
40.5% nonsense

11CIE72.7% missense
27.3% nonsense

5LI100% missense

HI: Harlequin ichthyosis.
CIE: congenital ichthyosiform erythroderma.
LI: lamellar ichthyosis.