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GROUP MEMBERS

NURUSHUHADA BT YAHYA (D20091035102)

FADILAH BT MAHMUD (D20091035094)

ROSNITAH BT YACOB (D20091035118) NUR ELIANA BT MOHMAD NOOR (D20091035093)

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STUDY CASE 1

A healthy four-year-old boy of a first degreeconsanguineous couple was noted by the parent

to have darkening of the urine to an almost

black color when it was left standing. He had anormal sibling, and there were no other medical

problems. Childhood growth and development

were normal. As a biochemist, discuss this case.

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ABOUT ALKAPTONURIA

Alkaptonuria is a rare

condition in which a

person's urine turns a dark

brownish-black color when

exposed to air especiallywhen left standing for a

period of time

A buildup of darkpigment in connective

tissues such as cartilage

and skin, is also

characteristic of thedisorder.

People of this

condition typically

develop arthritis, heart

and kidney problems.

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How it happen ????Mutation in the HGD gene.

The gene defect makes the body unable to properly

break down certain amino acids

a) Tyrosine

b) Phenylalanine

Substance called homogentisic acid builds up in the skin

and other body tissues

HA accumulates in the blood

The acid leaves the body throughurine

The urine turn brownish black when it

mix with air

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HGD GENE

The HGD gene provides instructions for making anenzyme called homogentisate oxidase

Homogentisate oxidase helps break down the amino

acids phenylalanine and tyrosine Mutations in the HGD gene impair the enzyme's role

Produce homogentisic acid(alkapton) accumulate inthe blood

Excess homogentisic acid causes damage to cartilage(ochronosis) and heart valves as well as precipitating askidney stones.