Below is a summary for the DHCR7 gene observed in research publications. This is not meant to take the place of medical advice.

What is Smith-Lemli-Opitz syndrome?

Smith-Lemli-Opitz syndrome happens when there are changes in both copies of the DHCR7 gene. These changes can keep the gene from working as it should.

Key Role

The DHCR7 gene plays an important role in cholesterol and steroid metabolism, the process by which cells make energy.


Because the DHCR7 gene is important for many different parts of the body, many people may have:

  • Heart defects
  • Lungs that are not fully formed
  • Poor feeding and constipation
  • Genital development issues
  • Kidney problems
  • Intellectual disability
  • Autism
  • Seizures 
  • Low muscle tone as an infant
  • High muscle tone as a child
  • Brain changes found on ultrasound
  • Self-harming behavior
  • Aggressive behavior

Do people who have Smith-Lemli-Opitz syndrome look different?

People who have Smith-Lemli-Opitz syndrome may look different. Appearance can vary and can include some but not all of these features:

  • Short height
  • Smaller than average head size
  • Low-set ears
  • Wide-set eyes
  • Large central front teeth
  • Blonde hair

How many people have Smith-Lemli-Opitz syndrome?

About 1 in every 10,000 to 1 in every 70,000 babies are born with Smith-Lemli-Opitz syndrome, depending on the group of people counted.


Support Resources



GeneReviews are a great resource to bring to your child’s clinicians. These publications provide a summary of current research on genetic conditions and information on ongoing care.

Check out the GeneReviews for DHCR7.


Research Article Summaries

We currently do not have any article summaries for DHCR7, but we add resources to our website as they become available.

The information available about DHCR7 is limited, and families and doctors share a critical need for more information. As we learn more from children who have this gene change, we expect our list of resources and information to grow.

Full versions of published research articles can be found on PubMed. PubMed is a National Institutes of Health (NIH) online database that is free. It has a collection of both medical and scientific research articles. A PubMed search for DHCR7 articles can be found here.

You can also visit the Simons Foundation’s SFARI Gene website to see information for researchers about this gene.


Research Opportunities

Simons Searchlight

Help the Simons Searchlight team learn more about DHCR7 genetic changes by taking part in our research. You can learn more about the project and sign up here.

External Research Opportunity: FaceMatch

FaceMatch is a platform that helps parents and doctors contribute to an international secure image database of both undiagnosed and diagnosed children across the globe. *This study is not affiliated with Simons Searchlight. Learn more about FaceMatch.


Family Stories

We do not currently have any stories from DHCR7 families.

Click here to share your family’s story!