Clinical Biochemical Genetics


The Biochemical Genetics Laboratory at the Kennedy Krieger Institute is located within the Johns Hopkins medical complex. The laboratory provides training in the diagnosis of inborn errors of amino acid , organic acid, fatty acid, sterol, creatine, and peroxisomal metabolism using a variety of techniques including amino acid analysis by anion exchange chromatography, organic acid analysis by gas chromatography/mass spectrometry, acylcarnitine analysis by tandem mass spectrometry, and sterol analysis by ion ratio gas chromatography/mass spectrometry, as well as numerous staple isotope gas chromatography/mass spectrometry methods. Exposure to the principles of newborn screening is also provided.

Upon successful completion of the training program, trainees are eligible to sit for the AMBGG Board Certification Exam in Clinical Biochemical Genetics.

Program History

The American Board of Medical Genetics first certified the Clinical Biochemical Genetics Training Program at Johns Hopkins in 1984. George Thomas, PhD directed this program from 1984 until the summer of 2005. The program was accredited by the ACGME in December, 2019. David Valle, MD is the Program Director and Lisa Kratz, PhD is the laboratory and training program director.  

Training Objectives

  • Demonstrate proficiency in all aspects of the following methods, including sample preparation, instrument operation and maintenance, data analysis, result interpretation, and generation of reports.
  • Gain experience in the laboratory diagnosis of inborn errors of amino acid, organic acid, and fatty acid metabolism, cholesterol biosynthesis, creatine biosynthesis and transport, and peroxisome metabolism.
  • Demonstrate the ability to direct all phases of a complex testing environment including report preparation and communication of results, laboratory quality control and assurance programs, and proficiency testing and be familiar with laboratory regulatory agency policies and procedures.
  • Fellows will complete their logbook cases in compliance with the ACGME requirements.

Meeting Training Goals

During the first year of training, fellows spend the majority of their time participating in all aspects of the clinical laboratory at Kennedy Krieger Institute, including but not limited to: learning laboratory techniques, data analysis and data interpretation. Each fellow is required to attend weekly Chart Review, the Department of Genetic Medicine (DGM) Journal Club where they will be the presenter at least once during their training, and Clinical Genetics Case Conference where they are expected to present interesting cases regularly. In addition the Fellow attends the monthly DGM Seminar series and the Greenberg Center Clinical Conference, both located at the Johns Hopkins Hospital (JHH) location.  There is an option to do a rotation at the State Newborn Screening Program at the Maryland Department of Health and Mental Hygiene (DHMH) to participate in the usual screening procedures.

During the second year of training, in addition to the continued participation in the clinical laboratory meetings and required Case Conference, Journal Clubs, and JHMI Seminars, each fellow takes two graduate level courses: Advanced Topics in Human Genetics and Molecular Mechanisms.  A passing grade is required for the Fellow to successfully complete the program.  In addition the Fellow will spend approximately 50% of their laboratory time participating in clinical laboratory testing and 50% of their time performing research. Finally, the Fellows are encouraged to attend the two week, Short Course in Mammalian Genetics in Bar Harbor, Maine, in July, as well as submit and present at the American Society of Human Genetics, American College of Medical Genetics, or the Society for Inherited Metabolic Disorders scientific meetings.

Obtaining Hands-on Experience

Trainees learn each test/technique by first, observing a staff member who routinely performs the test/technique, then performing the test/technique on quality control and/or previously tested patient samples.  Once the Fellow becomes proficient and obtains approval by the Laboratory Director, they will perform a given test/technique, on patient sample sets periodically throughout their fellowship.  


Supervision of all Fellows in the Postdoctoral Clinical Biochemical Genetics Training Program is performed by the Laboratory Training Director, Lisa Kratz, PhD. While in the clinical setting the Fellow is supervised by the clinic Attending.

Initially, Fellows review results of laboratory tests with the laboratory director.  Once the Fellow demonstrates an understanding of data evaluation and interpretation, they interpret the lab data and prepare reports for review by the laboratory director.

Outpatient Genetics Clinic occurs each Monday and Fellows will have an opportunity to attend clinic to observe the process of informed consent, diagnosis (explanation of results and testing), treatment, and follow-up of children and adults with Metabolic Disorders.  Biochemical Genetics fellows with Clinical Genetics training/hospital credentialing will be assigned outpatients in clinic and participate in Metabolism Call under the supervision of the Metabolic Attending. 

In specific instances, the Fellow will communicate results to the ordering physician or patient under the guidance of the laboratory director or patient physician, respectively.