# Extrarenal Clinical Features are Reported for Most Genes Implicated in Genetic Kidney Disease

## TL;DR

Most genes linked to kidney disease are also associated with non-kidney symptoms, which are more common in inherited conditions affecting children.

## Contribution

The study reveals that extrarenal features are commonly reported for genes involved in genetic kidney diseases, especially those with autosomal recessive inheritance.

## Key findings

- Extrarenal features were reported for 89% of the 255 genes examined.
- Genes associated with ciliopathies and CAKUT had the highest number of extrarenal features.
- Growth, musculoskeletal, and neurological systems were most commonly affected.

## Abstract

Genetic kidney disease is often suspected based on a family history of the disease or the presence of extrarenal features. This study examined how often a positive family history or syndromic features are found.

A total of 255 genes from the Genomics England “green” lists for congenital anomalies of the kidney and urinary tract (CAKUT) (n = 57), ciliopathies and cystic kidney diseases (n = 90), hematuria (n = 5), renal proteinuria (n = 55), and renal tubulopathies (n = 48) were examined for mode of inheritance and, in the Online Mendelian Inheritance in Man (OMIM), for reported clinical features in different systems (neurological, cardiac, etc.) that would be obvious on a history or physical examination.

Autosomal recessive (AR) inheritance was recorded for 148 of the 248 genes (60%) with an OMIM entry. Extrarenal features were associated with 221 genes (89%), including those causing hematuria (5, 100%), renal ciliopathies (86, 97%), CAKUT (52, 91%), renal tubulopathies (41, 85%), and proteinuric renal diseases (37, 76%).The median number of affected systems was 4 (range: 0–10). More extrarenal features were associated with CAKUT (4, 0–10) and the ciliopathies (5, 0–9) than with hematuria (2, 2–5), proteinuria (3, 0–7), and the tubulopathies (3, 0–7) (P < 0.00001). The most commonly-affected systems were growth and musculoskeletal (164, 66%), neurological (147, 59%), and ocular (133, 54%).

Extrarenal associations have been reported for most genes affected in genetic kidney disease, and are more common with pediatric-onset conditions with recessive inheritance. However, information is limited for how often extrarenal features are found in any individual.