 This protocol is designed to study the natural disease process of LINCL. We propose to assess the correlation between genotype genetic constitution and phenotype observable characteristics of late infantile neuronal ceroid lipofuscinosis LINCL in children diagnosed with LINCL in all stages. LINCL is a form of Batten disease that affects the brain of children and prevents it from functioning properly. These children are born with genetic changes called mutations that result in the inability of the brain to properly recycle proteins in the brain. The recycling failure leads to death of the nerve cells in the brain and progressive loss of brain function. Children with Batten disease are normal at birth but by age 2 to 4 have motor and vision problems which progress rapidly to death at age approximately 10 years old. There are no therapies available to treat the disease. This study is designed to run parallel to the gene transfer protocol, which will include 16 individuals in two groups: Group A will receive 9.0x1011 genome copies gc of the vector and Group B will receive 2.85x1011 gc; we anticipate that we will be able to capture a one-time genotype - phenotype snapshot for all n32, and an 18 months genotype - phenotype progression assessment for n16. 