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GTR Home > Tests > Fibrillinopathy NGS panel

Fibrillinopathy NGS panel

  • GTR Test IDHelp: GTR000592112.1
  • Last updated: 2022-12-23
  • Test version history

Clinical testHelp for Classic homocystinuria
Offered by HNL Genomics Connective Tissue Gene Tests

Indication

This is a clinical test intended for Help: Diagnosis, Mutation Confirmation

Clinical summary

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Imported from GeneReviews

Homocystinuria caused by cystathionine β-synthase (CBS) deficiency is characterized by involvement of the eye (ectopia lentis and/or severe myopia), skeletal system (excessive height, long limbs, scolioisis, and pectus excavatum), vascular system (thromboembolism), and CNS (developmental delay/intellectual disability). All four ‒ or only one ‒ of the systems can be involved; expressivity is variable for all of the clinical signs. It is not unusual for a previously asymptomatic individual to present in adult years with only a thromboembolic event that is often cerebrovascular. Two phenotypic variants are recognized, B6-responsive homocystinuria and B6-non-responsive homocystinuria. B6-responsive homocystinuria is usually milder than the non-responsive variant. Thromboembolism is the major cause of early death and morbidity. IQ in individuals with untreated homocystinuria ranges widely, from 10 to 138. In B6-responsive individuals the mean IQ is 79 versus 57 for those who are B6-non-responsive. Other features that may occur include: seizures, psychiatric problems, extrapyramidal signs (e.g., dystonia), hypopigmentation of the skin and hair, malar flush, livedo reticularis, and pancreatitis.

Clinical features

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Imported from Human Phenotype Ontology (HPO)

  • Arachnodactyly
  • Depression
  • Ectopia lentis
  • Glaucoma
  • Inguinal hernia
  • Homocystinuria
  • Lens subluxation
  • Mitral valve prolapse
  • Myocardial infarction
  • Myopia
  • Osteoporosis
  • Pancreatitis
  • Personality disorder
  • Scoliosis
  • Seizure
  • Stroke
  • Thromboembolism
  • Dental crowding
  • Pectus carinatum
  • Hypopigmentation of the skin
  • Atypical behavior
  • High palate
  • Tall stature
  • Cutis marmorata
  • Brittle hair
  • Global developmental delay
  • Kyphoscoliosis
  • Disproportionate tall stature
  • Biconcave vertebral bodies
  • Methioninuria
  • Limitation of joint mobility
  • Pectus excavatum
  • Failure to thrive
  • Hepatic steatosis
  • Visual impairment
  • Intellectual disability
  • Hyperhomocystinemia
  • Hypermethioninemia
  • Generalized osteoporosis
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Inheritance pattern

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Autosomal recessive inheritance

Conditions tested

Target population

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Individuals whose clinical findings are consistent with the specific disorder.

Citations

Not provided

Clinical validity

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Not provided

Clinical utility

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Not provided

Reviews

Clinical resources

Practice guidelines

  • ACMG ACT, 2021
    American College of Medical Genetics and Genomics, Newborn Screening ACT Sheet, Elevated Methionine +/- Elevated Homocysteine, Homocystinuria (Cystathionine beta-synthase deficiency), 2021
  • ACMG Algorithm, 2021
    American College of Medical Genetics and Genomics, Algorithm, Elevated Methionine +/- Elevated Homocysteine, 2021
  • ACMG ACT, 2012
    American College of Medical Genetics and Genomics, Transition to Adult Health Care ACT Sheet, Homocystinuria (CBS Deficiency), 2012

Molecular resources

Consumer resources

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