How is 1p36 Deletion Syndrome diagnosed?

1p36 Deletion Syndrome is diagnosed through specialized genetic testing, specifically chromosomal microarray analysis (CMA), which identifies a missing piece of genetic material at the end of the short arm of chromosome 1. Because symptoms can vary significantly, the diagnostic journey often involves a clinical evaluation by a medical geneticist followed by confirmation via molecular testing.

How is 1p36 Deletion Syndrome diagnosed?

The diagnostic process for 1p36 Deletion Syndrome typically begins when a pediatrician or specialist notices a combination of developmental delay, intellectual disability, and characteristic facial features. Because these features overlap with many other conditions, the "diagnostic odyssey"—the long, frustrating period of seeking answers—is common for families. A definitive diagnosis is achieved through a chromosomal microarray (CMA), which is a high-resolution test that detects small deletions or duplications in the DNA that standard karyotyping might miss.

What tests are used to confirm 1p36 Deletion Syndrome?

Once a clinician suspects 1p36 Deletion Syndrome, they will order specific tests to confirm the genetic anomaly. These include:

• Chromosomal Microarray (CMA): The gold-standard diagnostic tool to identify the terminal deletion on chromosome 1p36.


• Fluorescence In Situ Hybridization (FISH): Sometimes used to confirm the deletion or to test parents to see if the deletion was inherited or de novo.


• Clinical Evaluation: Assessment of physical traits, such as deep-set eyes, a pointed chin, and midface hypoplasia, which are common clinical markers for 1p36 Deletion Syndrome.

Which specialists should evaluate for 1p36 Deletion Syndrome?

If you suspect 1p36 Deletion Syndrome, it is vital to consult a clinical geneticist. General practitioners may be unfamiliar with this rare condition due to its prevalence of approximately 1 in 5,000 to 10,000 births. A geneticist can provide accurate interpretation of microarray results and guide your family through the differential diagnosis process, ensuring the condition is not confused with other genetic syndromes like Rett syndrome or Angelman syndrome.

Next steps

• Request a referral to a board-certified clinical geneticist for formal testing.


• Connect with the 22 members of the 1p36 Deletion Syndrome community on DiseaseMaps.org to share experiences and find support.


• Maintain a detailed log of developmental milestones to assist your specialists in their clinical assessment.

Medical disclaimer: This information is for educational purposes only and does not constitute medical advice, diagnosis, or treatment; always seek the advice of your physician or other qualified health provider with any questions regarding a medical condition.

References

• NIH Genetic and Rare Diseases Information Center (GARD): 1p36 deletion syndrome


• Orphanet: 1p36 deletion syndrome (ORPHA:1683)


• OMIM (Online Mendelian Inheritance in Man): Chromosome 1p36 deletion syndrome (#607872)


• 1p36 Deletion Support & Awareness (1p36DSA)