• ALKAPTONURIA

• ALKAPTONURIA

• Black urine disease or black bone disease is an inborn error of amino acid metabolism.
• It is a rare inherited genetic disorder of phenylalanine (Phe) and tyrosine (Tyr) metabolism.
• Autosomal recessive condition (both parents must have the gene in order to pass to their progeny).

COURSE OF THE DISEASE

• Mutation or defect in HGD gene which causes lack of the enzyme homogentisate dioxygenase (HGD).
• • This causes a build up of homogentisic acid (HGA) in the bones, cartilage and urine.
• • HGA is an intermediate in the degradation pathway of the amino acids (Phe & Tyr ) to the Krebs cycle.

INHERITANCE

• Alkaptonuria is inherited as an autosomal recessive trait.
• Recessive genetic disorders occur when an individual inherits the same abnormal gene for the same trait from each parent.

SYMPTOMS OF ALKAPTONURIA

• Urine becomes black when exposed to air.
• Osteoarthritis (mainly spine, hips, shoulders and knees).
• Black spots in the sclera of the eye (Ochronosis).
• Discolored ear and dark earwax.
• Heart valves are affected by the accumulation of HGA. Blue-black speckled discoloration of the skin.
• Kidney, prostate and bladder stones due to the build- up of HGA in the genito-urinary tract, during urine production.

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TREATMENT

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• The treatment of alkaptonuria is aimed at the specific symptoms.
• Activities that place significant physical stress to the spine and joints should be avoided.
• Patients receive anti-inflammatory medications or narcotics to treat joint pain.
• Physical and occupational therapy- to maintain the strength and flexibility of muscles and joints.
• Some individuals require surgical intervention.

REFERENCES

https://www.healthline.com/health/alkaptonuria

https://images.app.goo.gl/87rf2A8CrZy2ZeaS7

Thankyou

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By

Sreelakhmi.T

BSC ZOOLOGY

ROLL NO:13

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