The investigators are trying to learn more about the cause of kidney diseases such as Focal Segmental Glomerulosclerosis (FSGS) and Nephrotic syndrome by studying genetics. The investigators are interested in discovering which genes play a role in causing a predisposition to FSGS/NS. The investigators also want to learn why FSGS/NS can run in families. Participation in our study involves a saliva sample and a urine sample that you can give from home. There is no cost to participate. All information is kept private and confidential. The investigators also like to include healthy volunteers (parents, spouses) if interested/available but of course this is completely optional.

The investigators welcome anyone (with or without a family history) with unexplained, non syndromic FSGS, nephrotic syndrome, or proteinuria to join the study. Participation involves a saliva (or blood if it is preferable) sample and urine sample (if applicable). There is no cost to participate and the study can be done from home in most cases.

Inclusion Criteria:

• Subjects with FSGS (focal segmental glomerulosclerosis)
• Subjects with NS (nephrotic syndrome)
• Subjects with unexplained kidney failure (have had a transplant or on dialysis)
• Subjects with unexplained proteinuria
• Family members of a person with FSGS, NS, kidney failure, or unexplained protein in their urine
• Healthy volunteers

Exclusion Criteria:

• Patients whose kidney disease is already explained by another syndrome such as (Branchio Oto Renal Syndrome or Alports syndrome)
• Patients who already know the genetic cause of their kidney disease

We are recruiting subjects who have kidney disease, family members of a person with kidney disease, and healthy controls.