Table 3.

Genotype-Phenotype Correlations for Affected Gene and Variant Type Among 17 Index Patients and 25 Family Members With a Mono-allelic COL4A3 or COL4A4 Variant

	COL4A3	COL4A4	Pa
Number of individuals, n	8	34
Number of families, n	5	12
Median age at presentationb, y (range)	51 (4-66)	39 (6-61)	0.14
Median eGFR at presentationc, mL/min/1.73 m2 (range)	86 (14-136)	101 (36-128)	0.32
Proteinuria at presentation, n (%)	7 (100%)	22 (73%)	0.31
Extrarenal findingsd, n (%)	0 (0%)	2 (6%)	1.00
Median age at last FU, y (range)	55 (43-67)	52 (13-82)	0.38
Median eGFR at last FUc, mL/min/1.73 m2 (range)	84 (58-121)	73 (9-117)	0.52
End-stage kidney disease, n (%)	2 (25%)	4 (12%)	0.30
Proteinuria at last FU, n (%)	7 (100%)	20 (67%)	0.16

	Missense	Non-missense	Pa
Number of individuals, n	37	5
Number of families, n	16	1
Median age at presentationb, y (range)	39 (4-66)	48 (38-54)	0.19
Median eGFR at presentationc, mL/min/1.73 m2 (range)	95 (14-136)	102 (101-116)	0.32
Proteinuria at presentation, n (%)	25 (78%)	4 (80%)	1.00
Extrarenal findingsd, n (%)	2 (5%)	0 (0%)	1.00
Median age at last FU, y (range)	52 (13-82)	55 (46-80)	0.40
Median eGFR at last FUc, mL/min/1.73 m2 (range)	73 (9-121)	83 (67-105)	0.30
End-stage kidney disease, n (%)	6 (16%)	0 (0%)	0.57
Proteinuria at last FU, n (%)	24 (75%)	3 (60%)	0.60

Note: Percentages were calculated over all cases with available information.

Abbreviations: eGFR, estimated glomerular filtration Rate; FU, follow-up.

^aP values were calculated using Mann-Whitney U test for continuous variables and Fisher exact test for categorical variables.

^bAge at clinical presentation was determined retrospectively based on first symptom (glomerular hematuria and/or proteinuria) attributable to COL4A3 or COL4A4 variant.

^cCalculated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formula.

^dAuricular or ocular findings.