4577
Neonates showing a severe clinical phenotype , analogous to the early neonatal lethal disease occurring in mice homozygous for a null allele produced by targeted disruption of GBA , have been described elsewhere , but the specific mutations in these cases have not yet been characterized .
 None
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Disease 
Text: {0} 
Answer:
 None