Understanding Genetic Disorders and Enzyme Deficiencies

Genetic disorders are often caused by mutations in genes that code for specific enzymes. When an enzyme is deficient or non-functional, the metabolic pathway it controls can be disrupted, leading to the accumulation of substances that are normally broken down or processed. This accumulation can cause various health problems, manifesting as specific diseases. This question asks us to match common genetic disorders with the specific enzyme whose deficiency is responsible.

Matching Genetic Disorders with Enzyme Deficiencies

Let's analyze each disorder and its associated enzyme based on known biological facts about these conditions:

• Gaucher disease: This is a lysosomal storage disease caused by a deficiency of the enzyme glucocerebrosidase. This enzyme is needed to break down glucocerebroside, a type of fatty substance.
• Hunter syndrome: Another lysosomal storage disease, Hunter syndrome (also known as MPS II) is caused by a deficiency of the enzyme iduronate-2-sulfatase. This enzyme is involved in breaking down specific types of complex carbohydrates called glycosaminoglycans (GAGs).
• Tay-Sachs disease: A severe neurological lysosomal storage disorder caused by a deficiency of the enzyme hexosaminidase A. This enzyme is crucial for breaking down GM2 ganglioside, a fatty substance found in nerve cells.
• Phenylketonuria (PKU): This is a metabolic disorder caused by a deficiency of the enzyme phenylalanine hydroxylase. This enzyme converts the amino acid phenylalanine into tyrosine. Without functional phenylalanine hydroxylase, phenylalanine accumulates in the body.

Based on this information, we can create the following matching pairs:

• i. Gaucher disease matches with d. Glucocerebrosidase
• ii. Hunter syndrome matches with c. Iduronate-2-sulfatase
• iii. Tay-Sachs disease matches with b. Hexosaminidase A
• iv. Phenylketonuria matches with a. Phenylalanine hydroxylase

This gives us the matching sequence: i - d, ii - c, iii - b, iv - a.

Revision Table: Genetic Disorders and Enzyme Deficiencies

Additional Information: Understanding Metabolic Disorders

The disorders listed are examples of Inborn Errors of Metabolism, which are genetic conditions where the body cannot properly turn food into energy or break down certain substances. These errors are typically caused by defects in specific enzymes. Understanding these pathways and the role of enzymes is crucial in diagnosing and managing such conditions.

• Lysosomal Storage Diseases: Gaucher disease, Hunter syndrome, and Tay-Sachs disease fall under this category. Lysosomes are organelles within cells that contain enzymes to break down waste products. In these diseases, a specific lysosomal enzyme is deficient, leading to the buildup of undigested material within the lysosomes.
• Amino Acid Metabolism Disorders: Phenylketonuria is an example of a disorder affecting amino acid metabolism. Amino acids are the building blocks of proteins. Enzymes are required to process amino acids correctly. A defect here leads to the accumulation of specific amino acids or their byproducts.

Early diagnosis and intervention, such as dietary restrictions (as in PKU) or enzyme replacement therapy, can significantly impact the outcome for individuals with these genetic disorders.