Associated disorders

The DICER1 gene is associated with autosomal dominant DICER1-pleuropulmonary blastoma familial tumor predisposition syndrome (MedGen UID: 825667).

The DICER1 gene encodes a ribonuclease protein that is required by the RNA interference and small temporal RNA pathways to produce short RNA fragments that repress gene expression. Through this role in regulating the expression of genes, DICER1 is involved in many processes, including cell proliferation and cell differentiation.

DICER1-pleuropulmonary blastoma familial tumor predisposition syndrome
MedGen UID: 825667

Clinical condition
Individuals with a pathogenic DICER1 variant have an increased risk of developing pleuropulmonary blastoma, cystic nephroma, and thyroid neoplasia, including goiter, adenomas and differentiated thyroid cancer. Pleuropulmonary blastoma and cystic nephroma typically present in childhood. Females have an increased risk of developing ovarian sex cord-stromal tumors that include Sertoli-Leydig cell tumors, juvenile granulosa cell tumors, and gynandroblastoma. Multinodular goiter, adenomas, and differentiated thyroid cancer are typically adult-onset. Less frequently observed tumors associated with this condition include ciliary body medulloepithelioma, botryoid-type embryonal rhabdomyosarcoma, nasal chondromesenchymal hamartoma, pituitary blastoma, and pineoblastoma. Most tumors develop before age 40 (PMID: 24839956, 24761742, 21205968, 21036787, 25451712, 21266384, 19556464).

This tumor-susceptibility condition has low penetrance, which means that most individuals with a pathogenic variant in DICER1 will never develop tumors or cancer. The prevalence of this condition is currently unknown. Due to the rarity and reduced penetrance of DICER1 syndrome, specific lifetime risks for developing these tumors and cancers are currently unknown.

Gene information
The DICER1 gene is a member of the ribonuclease III family. It is involved in the generation of microRNAs, which modulate gene expression at the posttranscriptional level and act to repress gene expression. There is also evidence to suggest that DICER1 may be a tumor-suppressor gene Online Mendelian Inheritance in Man, OMIM®. Johns Hopkins University, Baltimore, MD. MIM Number: {606241}: {05/07/2015}: . World Wide Web URL:http://omim.org/ If there is a pathogenic variant in this gene that prevents it from functioning normally, the risk of developing certain types of cancers is increased.

DICER1 syndrome has autosomal dominant inheritance. This means that an individual with a pathogenic variant in DICER1 has a 50% chance of passing the condition on to their offspring. Once a pathogenic mutation is detected in an individual, it is possible to identify at-risk relatives who can pursue testing for this specific familial variant. Many cases are inherited from a parent, but approximately 20% occur spontaneously (i.e., an individual with a pathogenic variant has parents who do not have it) (PMID: 24761742). An individual with DICER1 syndrome has a 50% risk of passing that variant on to offspring.

There are no established screening or surveillance guidelines for individuals with a pathogenic DICER1 variant, but the International Pleuropulmonary Blastoma Registry has proposed the following recommendations International Pleuropulmonary Blastoma Registry. Accessed August 2015:

  • annual physical examination and targeted review of systems
  • imaging study type and frequency based on tumor type, patient age, and presence or absence of clinical findings

Formal surveillance for some of the rarer DICER1-related tumors may not be warranted, given the low penetrance, but the following has been suggested ( International Pleuropulmonary Blastoma Registry. Accessed August 2015:

  • baseline chest CT to evaluate for lung cysts or tumors in a patient of any age
  • baseline kidney CT or ultrasound examination in a patient diagnosed with pleuropulmonary blastoma
  • annual abdominal examination and monitoring for abdominal pain, swelling, or hematuria in a patient of any age, especially those younger than age 4 years
  • physical examination of the thyroid in a patient of any age
    • If thyroid gland asymmetry or a nodule is detected, perform a thyroid ultrasound examination to confirm and to determine if surveillance or a fine-needle aspiration biopsy is warranted.
    • If no nodules are detected, continue annual physical examinations and consider a repeat thyroid sonogram every 3–5 years.
    • If the patient has previously received chemotherapy or if chemotherapy is anticipated, perform a (baseline) thyroid ultrasound examination.
    • Based on clinical signs and symptoms of hypo- or hyperthyroidism, test thyroid function.
  • examination of all females of any age for signs and symptoms of precocious puberty or virilization and for masses in the abdomen or pelvis; performance of appropriate imaging and laboratory evaluations if detected
    • imaging—abdominal-pelvic US examination, MRI, or CT
    • laboratory testing—serum markers AFP, beta-HCG, LDH, inhibin A and B, estradiol, testosterone, CA125, and serum electrolytes (including calcium)
    • no current recommendations for laboratory screening in the absence of a mass or clinical findings of sex-hormone excess
  • education for women and for parents of young girls with a DICER1 pathogenic variant regarding the possible signs and symptoms of ovarian sex cord-stromal tumors (abdominal distension, precocious puberty, amenorrhea, signs of virilization)
  • evaluation of young children for ciliary body medulloepithelioma, including measurement of visual acuity; visual inspection of the eye and orbit
  • assessment of infants, children, and young adults for botryoid-type embryonal rhabdomyosarcoma by endoscopic evaluation of the bladder or by direct visualization of the cervix in the presence of signs or symptoms of hematuria or abnormal vaginal bleeding, respectively
  • assessment for nasal chondromesenchymal hamartoma by reviewing respiratory and feeding difficulties, rhinorrhea, epistaxis, visual disturbances, and otitis media
  • nasal endoscopy as warranted by ophthalmologic signs (e.g., ophthalmoplegia, proptosis, ptosis, hypotropia, enophthalmos) resulting from orbital involvement of the tumor
  • brain MRI at any age if there are signs of cortisol excess (which may suggest a pituitary blastoma) or increased intracranial pressure (suggestive of pineoblastoma)

Despite the lack of established medical management guidelines associated with this disorder, an individual’s cancer risk and medical management are not determined by genetic test results alone. Overall cancer risk assessment incorporates additional factors, including personal medical history, family history, and any available genetic information that may result in a personalized plan for cancer prevention and surveillance.

Even though data regarding pathogenic DICER1 is limited, knowing if a pathogenic variant is present is advantageous. At-risk relatives can be identified, enabling pursuit of a diagnostic evaluation. Further, the available information regarding hereditary cancer susceptibility genes is constantly evolving and more clinically relevant data regarding DICER1 are likely to become available in the near future. Awareness of this cancer predisposition encourages patients and their providers to inform at-risk family members, to diligently follow standard screening protocols, and to be vigilant in maintaining close and regular contact with their local genetics clinic in anticipation of new information.


Review date: September 2015

Assay and technical information

Invitae is a College of American Pathologists (CAP)-accredited and Clinical Laboratory Improvement Amendments (CLIA)-certified clinical diagnostic laboratory performing full-gene sequencing and deletion/duplication analysis using next-generation sequencing technology (NGS).

Our sequence analysis covers clinically important regions of each gene, including coding exons, +/- 10 base pairs of adjacent intronic sequence, and select noncoding variants. Our assay provides a Q30 quality-adjusted mean coverage depth of 350x (50x minimum, or supplemented with additional analysis). Variants classified as pathogenic or likely pathogenic are confirmed with orthogonal methods, except individual variants that have high quality scores and previously validated in at least ten unrelated samples.

Our analysis detects most intragenic deletions and duplications at single exon resolution. However, in rare situations, single-exon copy number events may not be analyzed due to inherent sequence properties or isolated reduction in data quality. If you are requesting the detection of a specific single-exon copy number variation, please contact Client Services before placing your order.

Gene Transcript reference Sequencing analysis Deletion/Duplication analysis
DICER1 NM_177438.2