Ornithine carbonyl transferase deficiency

What is Ornithine Carbonyl Transferase Deficiency

Ornithine Carbonyl Transferase Deficiency is a complex condition in which urea cycle become disturbs and abnormal production of ammonia occurs.

The female it is heterozygote without symptoms whereas in male individuals it is homozygote with infancy. This disease is arising in males and can affect them at any stage of life whereas in females it appears in the age of childhood.

Females are not only asymptomatic; some symptomatic females are also present. Symptoms in females are due to a mutation in genes of liver cells through the mechanism of lyonization. Late-onset males are present due to the total loss of enzymatic activity. Some male patients are also present with less activity of enzymes.

The appearance of disorder in newly born babies is commonly a disaster. Male influenced by late-onset OTC any background relations. These males suffer and the disease appears in the age of early childhood just like in newly born babies. Females with this disease may suffer from headaches similar to migraine. It is due to the higher level of protein intake.

Females which carry muted genes suffer from hyperammonemia related to stress in metabolic functions.  This is highly dangerous in females with intercurrent illness. A female suffering from this disease may fall into brain damage which leads to death.

There are highly multiple risks and causes of hyperammonemia due to the loss of urea cycle enzymes. Some indications are irritability, coma, asterixis, vomiting, somnolence, cerebral defects, and lethargy. Death is the last stage of hyperammonemia. This disease is highly related to defects in the urea cycle.

Background

This disease is highly related to defects in the urea cycle. In other words, OCT is a generally occurring disorder linked to the urea cycle.  When a mutated gene expresses itself, it synthesizes an abnormal enzymatic protein that is responsible to form functional ornithine. Due to abnormal carbamoyl phosphate and responsible protein ornithine, nonfunctional citrulline is produced.

This abnormal condition leads to diminished or reduced incorporation of ammonia. Due to less incorporation of ammonia symptoms of high blood pressure appear. Expression of the responsible gene takes place in the liver and it is mitochondrial in nature.

Introduction

It is an enzyme that is the constituent of the urea cycle which catalyzes the reactions between carbonyl and ornithine to form citrulline. It is mostly present in the mitochondria. Here this enzyme is used for the citrulline formation. This citrulline at the end will be changed into urea.

This enzyme is very important because without this enzyme ornithine and carbamoyl will accumulate within the body. This enzyme is controlled by the genes, so its deficiency may cause the disease not only in the person but also in the next progeny of the person.

There are three different types of OCT. Two types are found in males whereas 1 type of OCT is found in females. Neonatal-onset (defects arise after birth) and late-onset OCT commonly appears in males. Only late-onset OCT appears in females.

OCT (defected urea cycle enzyme disease) is commonly examined and seen in children which are linked with several types of malfunctions and disorders including hepatic diseases and high blood pressure disease (hyperammonemia).

This is caused due to abnormal transport of ornithine protein in a cellular organelle called mitochondria. Recently it is described that the phenotype of the ornithine synthesizing gene has a relationship with its genotype. And this is very beneficial for clinical practice. This disease is highly related to defects in the urea cycle.

In other words, OCT is a generally occurring disorder linked to the urea cycle. Females which carry muted genes suffer from hyperammonemia related to stress in metabolic functions.  This is highly dangerous in females with intercurrent illness.

A female suffering from this disease may fall into brain damage which leads to death. There are highly multiple risks and causes of hyperammonemia due to the loss of urea cycle enzymes. Some indications are irritability, coma, asterixis, vomiting, somnolence, cerebral defects, and lethargy. Death is the last stage of hyperammonemia.

Classification OCT based on its types

There are three different types of OCT. Two types are found in males whereas 1 type of OCT is found in females. Neonatal-onset (defects arise after birth) and late-onset OCT commonly appears in males. Only late-onset OCT appears in females.

Neonatal on-set OCT

Symptoms of OCT in newly born babies are severe and appear within one month after birth. Neonatal on-set OCT with indications of spams, vomiting, lethargy, and coma is dangerous, severe, and even lethal in children.

In numerous cases the death rate is high and patients die within a few months after appearing the disease. If children survive with OCT various neurological defects may appear in patients. OCT can be detected in the liver because its activity is not enough to detect.

Late on-set OCT

Late on-set OCD may appear in patients at several stages of life such as age at the time of birth, childhood, adulthood, or later in life. Patients with late on-set OCT are asymptotic at the age of 65 years. However, some cases are reported with fewer symptoms in late on-set OCT.

Female patients with Late on-set OCT

Patterns of indications and symptoms of late on-set OCD are not so simple in females. Symptoms and indications are highly variable in female patients. Some females are asymptotic and, in some cases, females are sympatric and die.

  • The relation between OCT type and mutated gene
  • Gene mutations that are responsible for muted OCT genes are variable.
  • Gene mutation for neonatal on-set OCT

Symptoms of Ornithine Carbonyl Transferase Deficiency

Deficiency of OCT is a complex condition because of variation in sex for example in the female it is heterozygote without symptoms whereas in male individuals it is homozygote with infancy. This disease is arising in males and can affect them at any stage of life whereas in females it appears in the age of childhood.

Females are not only asymptomatic; some symptomatic females are also present. Symptoms in females are due to a mutation in genes of liver cells through the mechanism of lyonization. Late-onset males are present due to the total loss of enzymatic activity. Some male patients are also present with less activity of enzymes.

The appearance of disorder in newly born babies is commonly a disaster. Male influenced by late-onset OTC any background relations. These males suffer and the disease appears in the age of early childhood just like in newly born babies. Females with this disease may suffer from headaches similar to migraine. It is due to the higher level of protein intake.

Lack of appetite

Due to less digestion, or less (conversion) of citrulline products their lack of appetite occurs.

Vomiting

Due to less digestion, the vomiting process occurs. It all occurs due to the accumulation of urea.

Drowsiness

It causes drowsiness, in person that lacks the required enzyme.

Coma

Due to high levels of ammonia in the blood, it may affect the brain so it can lead to ammonia.

High temperature

Due to urea accumulation, the high temperature of the body occurs. It may lead to fever-like feedings.

What are Causes of Ornithine Carbonyl Transferase Deficiency

It is an X-linked genetic disorder. In which an abnormal gene on the X-chromosome is present. But however, due to the reason of excessiveness, the disorder does not express its symptoms. Female carriers for this disorder have both of X-chromosome. But due to restiveness, it does not show itself.

But if males have defected genes, on X-chromosomes, they show the disorder because they only have one copy of the X-chromosome, which is dominant. Ornithine carbonyl transferase is a gene linked enzyme of the body, in mitochondria. It is responsible for the formation of urea. As it is gene linked, it can be transferred from generation to generation.

It commonly occurs in males, because it is an X-linked disorder. Genes responsible for the formation of ornithine carboxyltransferase are present on the X-linked chromosome’s shorter arm. The protein from this type of enzyme is encoded by this type of gene, in the form of mRNA. This RNA moves to the ribosomes and proteins are formed.

This protein then forms this type of enzyme. All these enzymes are mostly present in the mitochondrial matrix. The name of this gene is called ornithine carboxyltransferase precursor. Four types of mutations are present in patients.

One type of mutation is nonsense and the other type is a missense mutation. 50% of patients with neonatal on-set OCT have nonsense mutations with a single stop codon. Insertion or deletion bases may also be present. In this condition, the level of enzymatic protein is reduced greatly with nil functional activity. Another half of the individuals are with missense mutations.

How to Diagnose Ornithine Carbonyl Transferase Deficiency

This disease is minute, and it is very difficult to diagnose it, but we try to diagnose it. There are two methods of diagnosis.

Blood test method

In this method, the blood sample is taken and then tested. If ammonia level is high in blood, then it is taken as the disorder carrying humans, otherwise not.

DNA test method

In this method, DNA is analyzed if there is any defect is present in any gene of DNA then the problem is present otherwise not,

Treatment option for Ornithine Carbonyl Transferase Deficiency

It is an enzyme that is the constituent of the urea cycle which catalyzes the reactions between carbonyl and ornithine to form citrulline. It is mostly present in the mitochondria. Here this enzyme is used for the citrulline formation. This citrulline at the end will be changed into urea.

This enzyme is very important because without this enzyme ornithine and carbamoyl will accumulate within the body. This enzyme is controlled by the genes, so its deficiency may cause the disease not only in the person but also in the next progeny of the person.

There are three methods of the treatment as follows

  • Protein should remove the protein from his diet
  • There should be recommended medicine by a physician that should be taken so that it may get controlled.
  • If blood ammonia level extends too much, then Hemodialysis is done to remove the ammonia.

Summary

It is an enzyme that is the constituent of the urea cycle which catalyzes the reactions between carbonyl and ornithine to form citrulline.  It is mostly present in the mitochondria. Here this enzyme is used for the citrulline formation.

This citrulline at the end will be changed into urea. This enzyme is very important because without this enzyme ornithine and carbamoyl will accumulate within the body. This enzyme is controlled by the genes, so its deficiency may cause the disease not only in the person but also in the next progeny of the person.

There are three different types of OCT. Two types are found in males whereas 1 type of OCT is found in females. Neonatal-onset (defects arise after birth) and late-onset OCT commonly appears in males. Only late-onset OCT appears in females.

Its main function is to form urea. Here carbamoyl-phosphate is attached with the amino acid chain in such a way that it forms the most complex structure of the protein. The active site of the enzyme is located at the inner phase between the protein monomers Like every other enzyme, the function of this enzyme is catalyzed or catalyzed.

If due to some genetic disorders this enzyme is totally missing, then it cannot perform its function properly, in the urea cycle. So consequent nitrogen is not converted into ammonia, this ammonia does not change to urea. In simple words, urea. In simple words, the urea cycle did not work, and ammonia accumulated in the body, and blood.

Due to high levels of ammonia in the blood, it may affect the brain so it can lead to ammonia. High temperature Due to urea accumulation, the high temperature of the body occurs. It may lead to fever-like feedings.

It is an X-linked genetic disorder. In which an abnormal gene on the X-chromosome is present. But however, due to the reason of excessiveness, the disorder does not express its symptoms. Female carriers for this disorder have both of X-chromosome.

This method DNA is analyzed if there is any defect present in any gene of DNA then the problem is present otherwise not. There are three methods of the treatment as follows: Protein should remove the protein from his diet, there should be recommended medicine by a physician should be taken so that it may get controlled and if the blood ammonia level extend too much, then Hemodialysis is done to remove the ammonia

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