Introduction

Tyrosinemia type 1 is an autosomal recessive inherited metabolic disorder attributed to deficiency of fumarylacetoacetate hydrolase (FAH), which is a terminal enzyme in the metabolism of tyrosine. The gene for this enzyme has been mapped to the long arm of chromosome 15^[1]. While primarily synthesized in the liver, FAH is also synthesized at moderate amounts in kidneys, adrenal glands, lungs, heart, intestines, stomach, pancreas, lymphocytes and skeletal muscles^[1]. The HT1 frequency worldwide is about 1 in 100,000 individuals.^[2]

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Dr Akshay Wanvat

Resident Doctor, Department of Paediatrics, Grant Government Medical College and JJ Group of Hospitals, Mumbai