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Heather C. Mefford, MD, PhD

Heather C. Mefford, MD, PhD


On staff since August 2008

Children's Title: Attending Physician

Academic Title: Associate Professor

Research Center: Center for Integrative Brain Research

"Geneticists are driven to understand the genetic basis of disease because we believe this information will lead us to better treatments and cures. I am so fortunate to be able to interact with a great group of researchers in Seattle who are using technology to understand disease. The scientists and the physicians I work with are very innovative and collaborative, which creates an inspiring, fun and successful working environment."

Making a Difference

  • Mentoring Talented Junior Faculty

    An academic medical center and research institute, Seattle Children’s is dedicated to helping junior faculty establish research careers. Recently, several of our emerging genetics researchers have made significant contributions to their field.... cont.


Board Certification(s)
Clinical Genetics (MD)
Medical/Professional School
University of Washington, Seattle
University of Washington, Seattle, Medical Genetics
Pediatrics, Seattle Children's Hospital, Seattle
Medical Genetics, University of Washington, Seattle
Clinical Interests

Epilepsy genetics, microdeletion syndromes; chromosome rearrangements and copy number changes as a cause of birth defects, mental retardation or autism.

Awards and Honors

Award NameAward DescriptionAwarded ByAward Date
2013 Young Investigator AwardSociety for Pediatric Research 2013
Young Investigator Travel AwardAmerican Epilepsy Society Annual Meeting 2011
William K. Bowes, Jr. Award in Medical Genetics 2009
Finalist, American Society of Human Genetics Trainee Awards Competition, 2008 Annual Meeting, Postdoctoral Clinical Research Category 2008


Genotype-phenotype correlation in CC2D2A-related Joubert syndrome reveals an association with ventriculomegaly and seizures.
Journal of medical genetics , 2012 Feb: 49(2)126-37
Further clinical and molecular delineation of the 15q24 microdeletion syndrome.
Journal of medical genetics , 2012 Feb: 49(2)110-8
Rare copy number variants are an important cause of epileptic encephalopathies.
Annals of neurology , 2011 Dec: 70(6)974-85
Absence seizures with intellectual disability as a phenotype of the 15q13.3 microdeletion syndrome.
Epilepsia , 2011 Dec: 52(12)e194-8
Spectrum of MLL2 (ALR) mutations in 110 cases of Kabuki syndrome.
American journal of medical genetics. Part A , 2011 Jul: 155A(7)1511-6
Genetic contribution to common epilepsies.
Current opinion in neurology , 2011 Apr: 24(2)140-5
Epilepsy and the new cytogenetics.
Epilepsia , 2011 Mar: 52(3)423-32
Detection of copy number variation using SNP genotyping.
Methods in molecular biology (Clifton, N.J.) , 2011: 767243-52
Genetically complex epilepsies, copy number variants and syndrome constellations.
Genome medicine , 2010 Oct 5: 2(10)71
Copy number variation analysis in single-suture craniosynostosis: multiple rare variants including RUNX2 duplication in two cousins with metopic craniosynostosis.
American journal of medical genetics. Part A , 2010 Sep: 152A(9)2203-10
Exome sequencing identifies MLL2 mutations as a cause of Kabuki syndrome.
Nature genetics , 2010 Sep: 42(9)790-3
Recurrent 200-kb deletions of 16p11.2 that include the SH2B1 gene are associated with developmental delay and obesity.
Genetics in medicine : official journal of the American College of Medical Genetics , 2010 Aug 30
Genome-wide copy number variation in epilepsy: novel susceptibility loci in idiopathic generalized and focal epilepsies.
PLoS genetics , 2010 May 20: 6(5)e1000962
A recurrent 16p12.1 microdeletion supports a two-hit model for severe developmental delay.
Nature genetics , 2010 Mar: 42(3)203-9
Recurrent microdeletions at 15q11.2 and 16p13.11 predispose to idiopathic generalized epilepsies.
Brain : a journal of neurology , 2010 Jan: 133(Pt 1)23-32
Genotype to phenotype-discovery and characterization of novel genomic disorders in a "genotype-first" era.
Genetics in medicine : official journal of the American College of Medical Genetics , 2009 Dec: 11(12)836-42
Familial and sporadic 15q13.3 microdeletions in idiopathic generalized epilepsy: precedent for disorders with complex inheritance.
Human molecular genetics , 2009 Oct 1: 18(19)3626-31
A method for rapid, targeted CNV genotyping identifies rare variants associated with neurocognitive disease.
Genome research , 2009 Sep: 19(9)1579-85
Duplication hotspots, rare genomic disorders, and common disease.
Current opinion in genetics & development , 2009 Jun: 196-204
Duplication within the SEPT9 gene associated with a founder effect in North American families with hereditary neuralgic amyotrophy.
Human molecular genetics , 2009 Apr 1: 1200-8
Interstitial deletion of 11q in a mother and fetus: implications of directly transmitted chromosomal imbalances for prenatal genetic counseling.
Prenatal diagnosis , 2009 Mar: 283-6
15q13.3 microdeletions increase risk of idiopathic generalized epilepsy.
Nature genetics , 2009 Feb: 160-2
Recurrent rearrangements of chromosome 1q21.1 and variable pediatric phenotypes.
The New England journal of medicine , 2008 Oct 16: 1685-99
A recurrent 15q13.3 microdeletion syndrome associated with mental retardation and seizures.
Nature genetics , 2008 Mar: 322-8
Recurrent reciprocal genomic rearrangements of 17q12 are associated with renal disease, diabetes, and epilepsy.
American journal of human genetics , 2007 Nov: 1057-69
Use of fluorescent sequence-specific polyamides to discriminate human chromosomes by microscopy and flow cytometry.
Nucleic acids research , 2002 Jul 1: 2790-9
The complex structure and dynamic evolution of human subtelomeres.
Nature reviews. Genetics , 2002 Feb: 91-102


Presentations TitleEventLocationDate
CNVs in epilepsy, ASD and Intellectual disabilityInternational Child Neurology ConferenceBrisbane, Australia 2012
Microarrays and Whole Exome Sequencing Provide a Window into Developmental Brain DisordersPediatric Academic Societies Annual MeetingBoston, MA 2012
New Insights into the evaluation of the individual with Interllectual DisabilityAmerican College of Medical Genetics Annual CLinical Genetics MeetingVancouver, WAMarch 2011
Genomic approaches to epilepsy: Copy number variantsAmerican Epilepsy Society Annual meetingBaltimore, MD 2011
CNVs in epilepsyComing Together on Epilepsy Genetics WorkshopJackson Labs, Bar Harbor Maine 2011
Copy number variants in epilepsiesGenomic Disorders MeetingSanger Center, Hinxton, UK 2011
Copy number variants in epilepsy: Identification of novel susceptibility lociNorth East Epilepsy MeetingNewcastle Upon Tyne, England 2010
A Spectrum of Genomic DisordersDECIPHER Symposium Hinxton, UK 2010

Research Funding

Grant TitleGrantorAmountAward Date
3 of 7 Epi4K: Gene discovery in 4,000 epilepsy genomesNIH/NINDSSept. 30, 2011 - Sept. 30, 2016
4 of 7 Epi4K: Gene discovery in 4,000 epilepsy genomes NIH/NINDSSept. 30, 2011 - Sept. 30, 2014
7 of 7 Epi4K: Gene discovery in 4,000 epilepsy genomesNIH/NINDSSept. 30, 2011 - Sept. 30, 2016
A Genomic Approach to EpilepsyNIH/NINDS $$Feb. 15, 2010 - Jan. 31, 2014
Novel Genomic Rearrangements in Developmental Pediatric DisordersBurroughs Wellcome Fund $, $Jan. 18, 2010 - Aug. 31, 2016

Primary Office

University of Washington
UW Box 356320 - Genetics
1959 NE Pacific St
Seattle, WA 98195-6320

Additional Offices

Seattle Children's
OC.9.850 - Medical Genetics
4800 Sand Point Way NE
Seattle, WA 98105

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