About glycogen storage disease vi

What is glycogen storage disease vi?

Hers disease is a genetic metabolic disorder caused by a deficiency of the enzyme, liver phosphorylase. This enzyme is necessary to break down (metabolize) glycogen, a carbohydrate that is stored in the liver and muscle and used for energy. Deficiency of this enzyme results in the abnormal accumulation of glycogen in the body. Hers disease is one of a group of disorders known as the glycogen storage disorders. It is characterized by enlargement of the liver (hepatomegaly), moderately low blood sugar (hypoglycemia), elevated levels of acetone and other ketone bodies in the blood (ketosis), and moderate growth retardation. Symptoms are not always evident during childhood, and children are usually able to lead normal lives.

What are the symptoms for glycogen storage disease vi?

Ketosis symptom was found in the glycogen storage disease vi condition

Symptoms vary from person to person, and people with GSD6 may not have all the symptoms listed. GSD6 is usually a relatively mild disorder, although rare cases with more severe symptoms have been reported.

Symptoms of GSD6 usually begin in infancy or childhood and may include an enlarged liver (hepatomegaly), low blood sugar (hypoglycemia) or an increase in the amount of lactic acid in the blood (lactic acidosis). Hypoglycemia can also cause symptoms such as faintness, Weakness, hunger and nervousness. If present, hypoglycemia is usually mild and occurs more often during an illness. The symptoms of the disease are especially likely to occur when an individual does not eat for a long time.

Some children with GSD6 are shorter than average due to slow growth. They may also have muscle Weakness (hypotonia). Intellectual development is usually normal. Although symptoms of GSD6 may not be present during childhood, it has been reported that liver enlargement can be noted, even if no other symptoms are present. 

Many of the symptoms of GSD6 tend to improve as children get older, and most adults do not have symptoms. Liver enlargement often disappears by puberty and final adult height is often average. Muscle strength and tone are usually normal by adulthood as well. In untreated individuals, growth delays and weakening of the bone (osteoporosis) are common. People with GSD6 may be at an increased risk of having liver cancer or an enlarged heart (cardiomyopathy) in late childhood and adulthood.

What are the causes for glycogen storage disease vi?

GSD6 is caused by harmful changes (mutations) in the PYGL gene. This gene is responsible for telling the body how to make an enzyme called liver glycogen phosphorylase. This enzyme is responsible for breaking down glycogen. Glycogen is a form of energy that comes from carbohydrates and is stored in the liver. When the body needs more energy, glycogen in the liver is broken down by the PYGL gene product, glycogen phosphorylase. 

When there are mutations in the PYGL gene, there is not enough functioning glycogen phosphorylase to break down glycogen. Therefore, glycogen starts to build up in the liver cells, which causes an enlarged liver. This also means that the body does not get enough energy, which causes symptoms such as hypoglycemia and lactic acidosis.  

GSD6 is inherited in an autosomal recessive manner. Recessive genetic disorders occur when an individual inherits a non-working gene from each parent. If an individual receives one working gene and one non-working gene for the disease, the person will be a carrier for the disease, but usually will not show symptoms. The chance for two carrier parents to both pass on the non-working gene and, therefore, have an affected child is 25% with each pregnancy. The chance of having a child who is a carrier, like the parents, is 50% with each pregnancy. The chance for a child to receive working genes from both parents is 25%. The chance is the same for males and females. 

What are the treatments for glycogen storage disease vi?

Because symptoms of GSD6 are generally mild, the disorder usually requires no treatment other than to avoid prolonged periods without eating. Because glycogen is only broken down when stored energy needs to be used, eating frequent meals can prevent the need to break down glycogen. Levels of blood glucose should be monitored to make sure that the diet is working correctly. This will minimize the symptoms of the disease. In some patients, no other treatment is necessary. Frequent, small meals supplemented with uncooked cornstarch are recommended to avoid hypoglycemia. Some individuals may require a bedtime snack and/or cornstarch to prevent nighttime development of hypoglycemia. Even for children and adults with little to no hypoglycemic episodes, a bedtime dose of cornstarch is suggested. Uncooked cornstarch is a complex carbohydrate that is difficult for the body to digest; therefore, it maintains healthy blood sugar levels for a more extended period than most carbohydrates in food. Cornstarch therapy has been noted to improve energy, growth, bone density, well-being and liver size. 

Routine monitoring of blood glucose and ketone levels periodically as well as during periods of increased activity and illness is necessary. Due to the growth delays associated with GSD6, height, and weight should be measured annually to monitor growth. Bone density examinations are recommended after growth is complete.

The outlook for individuals with GSD6 is generally considered very good. However, it has been noted that there is a small increased risk with age for development of liver cancer (hepatic adenocarcinoma). Annual liver ultrasound examinations are recommended beginning at age five years to screen for pre-cancerous tumor formation. Further research is needed to completely understand the risk for liver cancer in adulthood.

Genetic counseling is recommended for affected individuals and their families. Other treatment is symptomatic and supportive.

What are the risk factors for glycogen storage disease vi?

The deficiency of glycogen breakdown enzyme leads to Glycogen Storage Disease VI. When the glycogen levels are not broken and used in an infant’s body, they accumulate in the liver. This accumulation results in enlarged liver and its improper functioning.

Glycogen is the complex sugar in our body stored for energy requirements. The excess and unused glycogen create GSD VI. It detects during infancy or the early ages of a child. It increases the amount of lactic acid in the blood, and the patient can not intake food for a long time.

Originally GSD VI was called 'Hers' Disease by the name of Henry-Gery Hers, and the description of GSD VI in 1959. With that, Glycogen Storage Diseases VI's main symptoms are Low blood sugars, enlarged liver, and increased glycogen content in the liver.

Risk factors:

Inherited diseases have a specific characteristic that they occur due to one main reason, and that is a genetic mutation.

  • Developments at an unusual defected orientation in a copy of genes from parents are the reason to bring it to the child.
  • Process of Ketosis (using fats as energy)
  • Cell Enlargement and Dysfunctionality in them.
  • Untested Pathogenic Variants in a family.
  • Incomplete Pregnancy Tests

If the symptoms are mild during birth, a child can grow a healthy life with a specific diet and a well-observed lifestyle.

Slow Growth,Bone Weakening,Ketosis,Enlarged Liver,Problems in Standing,Walking and Sitting
Allopurinol,Lipid-Lowering Drugs,Fibric Acid Derivatives,Iron Salts,Enzyme Replacements HMG-CoA.
Faintness,Weakness,Hunger,Nervousness,Muscle Weakness

Is there a cure/medications for glycogen storage disease vi?

An inherited disease due to unbroken complex sugars called glycogen is Glycogen Storage Disease VI. It occurs with unused glycogen in the liver and muscles resulting in large liver tissues.

With the original name of her disease, GSD VI detects after the birth of a baby, and a slower growth rate, feeding issues, and a weak heart of a baby. Furthermore, when Glycogen Branching enzymes are deficient, extra glycogen accumulates, termed Glycogen Storage Disease VI.

Types of GSDs:

Doctors categorized the disease of Glycogen Storage according to the seat (organ) it affects to:

- Type 0: Liver
- Type I: Liver, Kidney, Intestines, Blood Cells
- Type II: Muscles, Heart, Nervous System, Blood Vessels
- Type III: Liver, Skeletal Muscles, Blood Cells
- Type IV: Liver, Heart muscles, Brain, Skin, and Nervous Systems
- Type V: Skeletal Muscles
- Type VI: Liver, Blood Cells
- Type VII: Skeletal Muscles and Blood Cells
- Type IX: Liver
- Type XI: Liver, Kidney, and Intestines


  • Clinical Testing
  • Liver Biopsy
  • Genetic Molecular Testing: PGYL Gene copy testing
  • Liver Ultrasound.


A conventional diet with few restrictions on fats and carbohydrates is helpful to patients in leading a normal lifestyle. Treatments include:

  • Corn Starch Therapy: Uncooked Corn Starch
  • Routine blood monitoring
  • Bone Density Examinations
  • Eating Food in instalments at regular intervals for continuous breakage process of glycogen.
  • Genetic counselling
  • Prescribed Medications

Slow Growth,Bone Weakening,Ketosis,Enlarged Liver,Problems in Standing,Walking and Sitting
Allopurinol,Lipid-Lowering Drugs,Fibric Acid Derivatives,Iron Salts,Enzyme Replacements HMG-CoA.
Faintness,Weakness,Hunger,Nervousness,Muscle Weakness

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