Cystinosis as a lysosomal storage disease with multiple mutant alleles: Phenotypic-genotypic correlations

Table 1 Chromosomal mapping of some inherited proximal renal tubular acidosis

Inherited proximal RTA	Gene	Chromosomal mapping
Autosomal recessive	SLC4A4	4q21
Dent´s syndrome	CLCN5	Xp11.22
Cystinosis	CTNS	17p13.2
Tyrosinemia type 1	FAH	15q23-q25
Galactosemia	GALT	9p13
Wilson´s disease	ATP7B	13q14.3-q21.1
Fanconi Bickel Syndrome	SLC2A2	3q26.1-26.3

RTA: Renal tubular acidosis.

Table 2 Summary of mutation variants of CTNS gene and with its phenotypic correlation

Phenotype	Mutation
Five nephropathic:	CTNS, GLY95TER and CTNS, 2-BP DEL, 397TG[58], CTNS, TRP138TER[58,73].
3 by Town et al[58]
2 forms by Shotelersuk et al[66]	CTNS, GLY169ASP and CTNS, 5-BP DEL, NT545[66].
Two nephropathic forms in adolescents	CTNS, 4-BP DEL, 18GACT[58,65], CTNS, 57-KB DEL[61], originally reported by Town et al[58] as a 65-kb deletion
Two atypical nephropathic	CTNS, VAL42ILE, CTNS, IVS7AS, C-G, -10[67]
Two ocular non-nephropathic	CTNS, IVS10AS, C-G, -3, CTNS, GLY197ARG[45]
Three forms by Phornphutkul et al[68]	CTNS, -295G-C[68] CTNS, -303G-T, CTNS, 1-BP INS, 303T[68]
Nephropathic
Ocular non-nephropathic
Nephropathic	CTNS, GLY339ARG[69]
Adolescent nephropathic	CTNS, ASN323LYS[70]
Atypical nephropathic	CTNS, GLY110VAL[62]
Adolescent nephropathic Atypical nephropathic	CTNS, SER139PHE[65]