G-1-P Screen (Galactose-1-Phosphate Uridyl Transferase)

Pathology category

Biochemistry - referred tests

Code

G1PU

Referral code

Request form

Test information

PLEASE SEND SAMPLE MON – THURS, as needs to be received by referral laboratory within 24 hours of collection. If required urgently please contact the laboratory prior to sending.Used in the diagnosis of Classical Galactosaemia: Lactose (glucose-galactose) is cleaved in the gut and the galactose absorbed. G1PUT is one enzyme in the pathway that converts galactose to glycogen. Deficiency causes increased levels of galactose-1phosphate and galactitol which causes cataracts on its accumulation. Urine reducing substances should be positive If high suspicion index, place baby onto a galactose/lactose restricted diet until results back

Guidelines

Pre-analytical

If transfused measure Galactose-1-phosphate (Li Hep whole blood) or do GPUT on mother.

Reference range

see report

Tube type

Tube type info

Li Hep whole blood

Special requirements

WHOLE BLOOD or BLOOD SPOT

Minimum volume

0.5 mL

Assay frequency

TAT Inpatient (urgent)

TAT Inpatient

4 weeks

TAT GP/Outpatient

4 weeks

Referral lab

Depts of Blood Sciences and Metabolic Biochemistry, Birmingham Children's Hospital