Table 2

NPHP6/CEP290 sequence variants of unknown significance

Family (individual)Country of originNucleotide alteration(s)*Alteration(s) in coding sequence†Exon (segregation)PCAge at ESRD‡ [years]Pheno- typeOcular features (age of diagnosis, years)Central nervous system features (other)
?, Second mutation not found; AT, ataxia; CVA, cerebellar vermis aplasia/hypoplasia; ESRD, end-stage renal disease; het, heterozygous in affected individual; JBTS, diagnosed with Joubert syndrome; M, mutation identified in mother; MR, mental retardation/psychomotor retardation; Mwt maternal sequence is wild type; ND, no data or DNA available; P, mutation identified in father; PC, parental consan-guinity; SLSN, diagnosed with Senior–Løken syndrome; RC, retinal coloboma.
*All mutations were absent from at least 188 chromosomes of healthy controls.
†Evolutionary conservation: NC, non-conserved; C. i., Cionaintestinalis.
‡All patients had renal ultrasonography results compatible with nephronophthisis (increased echogenicity and/or corticomedullary cysts).
‡Previously published.23
F459 (II-2)USAA1991G, ?‡D664G, ? (NC)21 (het,Mwt)NDJBTSNDCVA, AT, MR, RC (hepatic fibrosis, hearing loss)
A854 (II-9)Pakistan7311-7313delGAA, ?K2437del (C. i.), ?55 (het, ND)+NPHPNoneNone