What is Inborn Errors of Metabolism and Rare Disease?
Inborn errors of metabolism are genetic disorders in which the body cannot convert food (carbohydrates, proteins and fats) into energy and other necessary elements like Aminoacids and sterols. These disorders are usually caused by gene defects that make a particular enzyme defective or deficiencies of the substances that activate the enzymes, or faulty transport of compounds. Enzymes are proteins that help in converting food in to energy, which is required to do work. If the food is not broken down properly it may produce toxins that cause medical problems including growth, problems in the newborn such as poor feeding, vomiting, diarrhea, dehydration, temperature instability, seizures; and altered level of consciousness. Inborn errors of metabolism are now often referred to as congenital metabolic diseases or inherited metabolic diseases.

Rare Genetic Diseases
The rare genetic disease and disorders are caused due to abnormalities in the gene, chromosome and mitochondrial DNA. Genes are the basic unit of life and even the minutest abnormality in genes can have drastic effects on the body and general development. Genes are a storehouse of information. Because of the complexity of the gene pool, some defects may arise in the transition of information that a single gene holds. Both environmental factors and genetic factors are responsible for causing most of the reported diseases. In case of genetic diseases, the causal reason is attributed to defects in the patient's genetic content (genome). Genetic diseases are categorized under four groups, based on the cause, viz. monogenic (mutation in a single gene, e.g. sickle cell anemia), polygenic (mutation in more than one gene, e.g. Alzheimers disease), chromosomal (affecting chromosome, e.g. Down syndrome) and mitochondrial (affecting mitochondrial DNA, e.g. Leigh syndrome).

Mode of Inheritance
Inborn errors of metabolism occur as a result of mutations in certain genes. However, inheriting a gene with a mutation from only one parent doesn't always mean that you are at risk for the disease. Everyone has two copies of most genes - one copy from their mother and one from their father. Sometimes it only takes one damaged copy of a gene to cause a disease while other times it takes two. In fact, there are many different ways to inherit diseases and other traits.

•Autosomal Recessive
•Autosomal Dominant
•X-linked recessive
•X-linked dominant
•Mitochondrial Inheritance