inheritance.<unk>  is an autosomal recessive disorder, which means the defective gene responsible for the disorder is located on an autosome (chromosome 17 is an autosome), and two copies of the defective gene (one inherited from each parent) are required in order to be born with the disorder. The parents of an individual with an autosomal recessive disorder both carry one copy of the defective gene, but usually do not experience any signs or symptoms of the disorder. Unlike galactose-1-phosphate uridyltransferase deficiency, the symptoms of<unk>  are relatively mild. The only known symptom in affected children is the formation of cataracts, due to production of galactitol in the lens of the eye. Cataracts can present as a failure to develop a social smile and failure to visually track moving objects. Gene structure The human<unk> 1 gene contains 8 exons and spans approximately 7.3 kb of genomic DNA. The<unk> 1 promoter was found to have many features in common with other housekeeping genes, including high GC content, several copies of the binding site for the Sp1 transcription factor and the absence of TATA-box and CCAAT-box motifs typically present in eukaryotic polymerase II promoters. Analysis by 5-prime-RACE PCR indicated that the<unk> 1 mRNA is heterogeneous at the 5-prime end, with transcription sites occurring at many locations between 21 and 61 bp upstream of the ATG start site of the coding region. In vitro translation experiments of the<unk> 1 cDNA indicated that the protein is cytosolic and not associated with endoplasmic reticulum membrane.
Galactokinase deficiency
Hexokinase deficiency
Galactose epimerase deficiency
Enolase deficiency
Glutaminase deficiency
Ornithine aminotransferase deficiency
Malonyl-CoA decarboxylase deficiency
Pyruvate kinase deficiency