Guthrie test

From Embryology

Introduction

Dr Robert Guthrie

A blood screening test developed by Dr Robert Guthrie (1916-95) at University of Buffalo. The test is carried out on neonatal (newborn) blood for a variety of known genetic disorders.


Blood is collected using a heelprick and spotted onto a test sheet to dry for later testing. Different countries and medical services have different policies on not only what will be tested for but also how long the test card will be kept following analysis. Check your local service for specific information.

Diagnosis Links: Prenatal Diagnosis | pregnancy test | amniocentesis | chorionic villus sampling | ultrasound | Alpha-Fetoprotein | Pregnancy-associated plasma protein-A | Fetal Blood Sampling | Magnetic Resonance Imaging | Computed Tomography | Non-Invasive Prenatal Testing | Fetal Cells in Maternal Blood | Preimplantation Genetic Screening | Comparative Genomic Hybridization | Genome Sequencing | Neonatal Diagnosis | Category:Prenatal Diagnosis | Fetal Surgery | Classification of Diseases | Category:Neonatal Diagnosis

Some Recent Findings

  • Newborn hearing screening and genetic testing in 8974 Brazilian neonates.[1]"We have found 17 individuals who failed in transient otoacoustic emissions (TOAE). Among them, we detected 4 homozygous newborns for 35delG mutation and 3 individuals with A827G mutation in the MTRNR1 mitochondrial gene."
  • Whole genome microarray analysis, from neonatal blood cards. [2]] "Neonatal blood, obtained from a heel stick and stored dry on paper cards, has been the standard for birth defects screening for 50 years. Such dried blood samples are used, primarily, for analysis of small-molecule analytes. More recently, the DNA complement of such dried blood cards has been used for targeted genetic testing, such as for single nucleotide polymorphism in cystic fibrosis. Expansion of such testing to include polygenic traits, and perhaps whole genome scanning, has been discussed as a formal possibility. However, until now the amount of DNA that might be obtained from such dried blood cards has been limiting, due to inefficient DNA recovery technology. ...Together, these data suggest that DNA obtained from less than 10% of a standard neonatal blood specimen, stored dry for several years on a Guthrie card, can support a program of genome-wide neonatal genetic testing."

Routine Screened Disorders

This list may differ between countries.

  • Phenylketonuria (PKU)
  • Biotinidase Deficiency (OMIM)
  • Congenital Adrenal Hyperplasia (CAH) (OMIM)
  • Congenital Hypothyroidism (CH)
  • Congenital Toxoplasmosis
  • Cystic Fibrosis (CF) (OMIM)
  • Galactosemia (GAL) (OMIM)
  • Homocystinuria (OMIM)
  • Maple Syrup Urine Disease (MSUD) (OMIM)
  • Medium-Chain Acyl-CoA Dehydrogenase Deficiency (MCAD) (OMIM)
  • Toxoplasma gondii IgM antibodies[3]

Australia

NSW Newborn Screening Programme

NSW Newborn Screening Programme

Each year test more than 90,000 babies and detects about 90 who need urgent assessment and treatment. In NSW and Victoria, the bloodspot cards are currently stored indefinitely.

  • Phenylketonuria (PKU) - 1 in 10,000 live births (about 10 babies per year). PKU causes high blood levels of phenylalanine and severe intellectual disability. A diet low in phenylalanine, started in the first two to three weeks results in normal development.
  • Primary congenital hypothyroidism - 1 in 3,500 live births (about 26 babies per year). It is caused by the absence or abnormal formation or function of the thyroid gland. This causes growth and intellectual disability if not treated. Medication with thyroid hormone started early, results in normal growth and development.
  • Cystic Fibrosis (CF) - 1 in 2,500 live births (about 34 babies per year). Without treatment babies develop chest infections and often have very serious failure to thrive. Early institution of treatment greatly improves the health of babies with CF. Newborn bloodspot screening detects about 95% of babies with CF but also detects a few babies who may only be healthy carriers. For these babies a sweat test at about six weeks of age determines whether the baby has CF or is a healthy carrier.
  • Galactosaemia - 1 in 40,000 births (about 1-3 cases per year). Babies cannot process galactose, a component of lactose. Life-threatening liver failure and infections can occur. A galactose-free diet instituted in the first week is life saving.
  • Rarer metabolic disorders - Some fatty acid, organic acid and other amino acid defects can now be detected using Tandem Mass Spectrometry. These much rarer metabolic disorders affect about 15 – 18 babies per year. Early detection is important as diet and medications can treat most of these disorders. Without appropriate management they can cause severe disability or death.

Potential uses and access of stored bloodspots

  • Identified cards may be used for family benefit or research and only with separate consent obtained before testing.
  • Non-identifiable cards (identifiers permanently removed) may be used for research approved by a Health Research Ethics Committee – consent is not required.
  • Parents have a right to access their child’s information. Other access requires parental consent except where there is a court order, to date this has not occurred.


Genetics services in NSW - coordinated by the NSW Genetics Service Advisory Committee, which is supported by the Statewide Services Development Branch of the Strategic Development Division, NSW Department of Health. (Information from NSW Health - Newborn Bloodspot Screening Policy 13-Nov-2006)


Links: NSW Genetics Health

USA

State laws mandate that blood be drawn from all newborn infants to screen for health-threatening conditions.

References

  1. <pubmed>20538352</pubmed>
  2. <pubmed>19624846</pubmed> | BMC
  3. The national neonatal screening programme for congenital toxoplasmosis in Denmark: results from the initial four years, 1999-2002. Schmidt DR, Hogh B, Andersen O, Fuchs J, Fledelius H, Petersen E. Arch Dis Child. 2006 Aug;91(8):661-5. PMID: 16861484]


Reviews

Articles

  • Changing incidence of neonatal hypermethioninaemia: implications for the detection of homocystinuria. Whiteman PD, Clayton BE, Ersser RS, Lilly P, Seakins JW. Arch Dis Child. 1979 Aug;54(8):593-8. PMID: 507913 | PMC1545774


Search PubMed

Search Pubmed: Guthrie test | neonatal blood spot test

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Cite this page: Hill, M.A. (2024, March 28) Embryology Guthrie test. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Guthrie_test

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© Dr Mark Hill 2024, UNSW Embryology ISBN: 978 0 7334 2609 4 - UNSW CRICOS Provider Code No. 00098G