Functional analysis of a childhood case with compound heterozygosity for MTTP c.619-5_619-2del and p.L435H, having severe liver fibrosis but no typical abetaliporoteinaemia symptoms, found that p.L435H abolished MTP activity, whereas the intronic variant resulted in 26% of transcripts being normally spliced, allowing limited MTP expression.32 The gene discussed is MTTP; the disease is Hepatic fibrosis.