Key enzyme in the regulation of glycerol uptake and metabolism. ATP + glycerol = ADP + H(+) + sn-glycerol 3-phosphate Polyol metabolism; glycerol degradation via glycerol kinase pathway; sn-glycerol 3-phosphate from glycerol: step 1/1. In sperm and fetal tissues, the majority of the enzyme is bound to mitochondria, but in adult tissues, such as liver found in the cytoplasm. Highly expressed in the liver, kidney and testis. Isoform 2 and isoform 3 are expressed specifically in testis and fetal liver, but not in the adult liver. The disease is caused by variants affecting the gene represented in this entry. Belongs to the FGGY kinase family.