Table 1.
Characteristics of the 677 affected individuals (501 families) sequenced by the Irish Kidney Gene Project (IKGP)
| Characteristics | Total sequenced (n = 677) | Total variants identified (n = 387) | Unsolved (n = 290) | P value |
|---|---|---|---|---|
| A priori clinical diagnosis, n (%) | ||||
| PKD | 241 (35.6) | 205 (53) | 36 (12.4) | < 0.001 |
| CAKUT | 85 (12.6) | 12 (3.1) | 73 (25.2) | |
| Chronic GN | 112 (16.5) | 24 (6.2) | 88 (30.3) | |
| TIKD | 75 (11.1) | 49 (12.7) | 26 (9) | |
| AS/FSGS | 72 (10.6) | 57 (14.7) | 15 (5.2) | |
| Others | 18 (2.7) | 13 (3.3) | 5 (1.7) | |
| uCKD | 74 (10.9) | 27 (7) | 47 (16.2) | |
| Recruited from, n (%)1 | ||||
| Monogenic kidney disease study | 138 (20.4) | 56 (14.5) | 82 (28.3) | < 0.001 |
| PKD study | 208 (30.7) | 177 (45.7) | 31 (10.7) | |
| GKD clinic | 331 (7.8) | 154 (39.8) | 177 (61) | |
| Median age, yrs (range) | 53 (18–93) | 54 (18–88) | 51 (18–93) | 0.018 |
| Age in years at onset of disease, n (%) | ||||
| < 18 (childhood onset) | 118 (17.4) | 66 (17.1) | 52 (17.9) | 0.142 |
| ≥ 18 (adult onset) | 450 (66.5) | 274 (70.8) | 176 (60.7) | |
| Unavailable | 109 (16.1) | 47 (12.1) | 62 (21.4) | |
| ESKD, n (%) | ||||
| Yes | 440 (65) | 228 (58.9) | 212 (73.1) | 0.001 |
| No | 215 (31.8) | 142 (36.7) | 73 (25.2) | |
| Missing | 22 (3.2) | 17 (4.4) | 5 (1.7) | |
| Median age at onset of ESKD, [IQR] | 30 [20–43] | 30 [21–44] | 30 [18–43] | 0.425 |
| Sex | ||||
| Male | 358 (52.9) | 196 (50.6) | 162 (55.8) | 0.163 |
| Female | 319 (47.1) | 191 (49.4) | 128 (44.2) | |
| FHx of CKD, n (%) 2 | ||||
| Yes | 500 (73.9) | 336 (86.8) | 164 (56.6) | < 0.001 |
| No | 140 (20.7) | 43 (11.1) | 97 (33.4) | |
| Unavailable | 37 (5.4) | 8 (2.1) | 29 (10) | |
| Self-reported ethnicity | ||||
| Irish | 646 (95.4) | 373 (96.4) | 273 (94.2) | 0.551 |
| Other Europeans | 18 (2.7) | 8 (2.1) | 10 (3.4) | |
| Black | 8 (1.2) | 4 (1) | 4 (1.4) | |
| Asian | 5 (0.7) | 2 (0.5) | 3 (1) | |
AS Alport syndrome, CAKUT congenital anomalies of the kidney and urinary tract, CKD Chronic kidney disease, ESKD end stage kidney disease, GKD genetic kidney disease, IQR Interquartile range, FHx family history, FSGS focal segmental glomerulosclerosis, GN glomerulonephritis, PKD polycystic kidney disease, uCKD CKD of uncertain aetiology, TIKD tubulointerstitial kidney disease, Yrs years
1In total, 677 patients were reviewed in the genetic kidney disease (GKD) clinic, recruited and bio-banked for the evaluation and management of nephropathy. Included in this large cohort, two groups of patients were previously published in the Monogenic Kidney Disease Study [11] and PKD study [23]; these are grouped separately for clarity
2A positive family history of kidney disease that was reported by the patient (either a 1st-degree relative (parent, child, or sibling) or a 2nd -degree relative (grandparent, aunt, uncle, niece, nephew, or cousin)