Nonketotic hyperglycinemia, NKH

Detect code ︰
NKH

Pathogenesis ︰
Nonketotic hyperglycinemia (NKH) for autosomal recessive genetic disease, the cause for the glycine cleavage enzyme complex (glycine cleavage enzyme complex, referred to as GCS) abnormalities caused by the enzyme by the P, T, H, L four protein composition, current research shows that nearly 80% NKH patients are caused by abnormal protein because of P and another near 10-15% of the patients due to abnormal T protein. P protein, glycine decarboxylase (GLDC) gene product; and T protein aminomethyltransferase (AMT) gene product.

Clinical symptoms ︰
Non-keto high glycine can be divided into neonatal hyperbilirubinemia type (neonatal type) and late onset (late-onset type) the two types.
Neonatal type more common in a few days after birth, neurological symptoms will appear and rapidly deteriorating, there will be low muscle tone, low Moro test reaction, epilepsy, asphyxia, lethargy or coma. Most of the patients died within a few weeks, after this period of time while still alive there is a serious developmental delay mental exercise phenomenon. In addition, there is also likely to attack various types of cramps, myoclonic epilepsy from the onset of epilepsy Tai may have happened, have hiccups situation is also very common. Neonatal period there will be very clear with low muscle tension, and then will gradually become stiff muscles.
Late onset cases in the neonatal period will not have abnormal symptoms, and then will be gradually developed various degrees of neurological symptoms, their age of onset ranging from infancy to adolescence. [The above information is extracted from the rare disease foundations]

Detected items ︰
GLDC and AMT gene

Detection Method ︰
Coding region sequencing

Sample type / volume ︰
Whole blood 5 ml.

Collection tube ︰
Purple head EDTA mining vessel.

Detect costs ︰
Call contact

Detect Time ︰
2 weeks

Prenatal diagnosis ︰
Can be mined villi (10mg and above) or amniotic fluid (10ml).

Genetic approach ︰


Prevalence ︰
1 / 12, 000 (Finland); Taiwan no statistical data

Gene location ︰
GLDC gene: the region on chromosome 9p
AMT gene: located on chromosome region 3p21.

Genetic testing
Limitations ︰
1. The molecular genetic testing to direct gene sequencing method, detection with a result of patients or persons in GLDC gene and the performance of sub-AMT gene (exon) regions whether pathogenic mutations happen, if for large fragment deletion of sequences or non-detection zone mutation can not be learned from this test.
2. If the cause of patients with this gene caused by non-, they can not be detected by this test.
3. Report of the accuracy rate of 97%, the results of clinical reference for physicians.