A novel missense mutation in the SLC6A19 gene in a Chinese family with Hartnup disorder

Abstract

We found a novel homozygous mutation of G284R in the transmembrane domain of the SLC6A19 transporter in the proband, with typical dermatologic and neurologic manifestations and increased levels of urinary neutral amino acids.

Pellagra: a review with emphasis on photosensitivity

“…Possible compounds include thiamine, riboflavin, pyridoxine, vitamin C and zinc 108,121 . The absence of mucosal involvement in drug‐induced pellagra and Hartnup disease is consistent with this explanation 97,98 . Similarly, the thickening of skin over bony prominences is an inconsistent feature of pellagra that appears to be limited to niacin deficiency caused by an inadequate diet.…”

“…Thus, chronic trauma with hypertrophic repair is a more likely explanation for this cutaneous feature of pellagra rather than niacin deficiency itself. As with mucosal involvement, this explanation is supported by the absence of this cutaneous feature in drug‐induced pellagra and Hartnup disease 97,98 . Occasionally, sebaceous gland changes in pellagra patients are independent of sun exposure and resemble seborrhoeic dermatitis, raising the possibility of riboflavin deficiency 108,121…”

“…The rash is worse during the spring and summer months; as in pellagra, the skin is dry, scaly, hyperkeratotic and pigmented 96 . Of note is the absence of reports of either mucosal involvement or skin hyperkeratosis over bony prominences 97,98 . Both of these features have been reported for dietary variants of pellagra cases 69,99 …”

Novel Mutation in SLC6A19 Causing Late-Onset Seizures in Hartnup Disorder

“…SLC6A19 encodes the amino acid transporter B 0 AT1, which cotransports Na + and a broad range of neutral amino acids from the luminal compartment into the cells [4]. To date, about 20 mutations in SLC6A19, including missense, splicing, and small deletions and insertions, have been reported [5][6][7]. We recently examined a Korean boy with Hartnup disorder with novel mutations of the SLC6A19 gene.…”

Collectrin and ACE2 in renal and intestinal amino acid transport

“…Twenty-one additional mutations were further described to cause the disease, including deletions, missense, nonsense and splice site mutations on the gene SLC6A19, as depicted in Figure 4. [90][91][92][93] Most of the patients are compound heterozygous, which could partially contribute to the variable symptoms observed in patients ( Table 2). …”