Q. What is dysmorphology?
dys = abnormality morphology = the study of form
A. Dysmorphology is specialized area of pediatrics dedicated to the understanding of the etiology (cause) and pathogenesis (what went wrong in development) of birth defects and developmental problems. The field is the legacy of the late David W. Smith, former Professor of Pediatrics at the University of Washington in Seattle. Trained as an endocrinologist, Dr. Smith recognized early in the course of his career that many children sent to him for problems of growth had multiple other developmental abnormalities and no evidence of a problem with hormone function. He spent his career describing patterns of anomalies in children to help parents understand the natural history of the condition (what it meant to have the diagnosis) and the recurrence risk (the possibility that the problem would happen again in another pregnancy). Smith’s Recognizable Patterns of Human Malformation (now in its 5th edition authored by Kenneth Lyons Jones, Professor of Pediatrics, University of California, San Diego) is the compilation of those efforts.
Q. What kind of physician is a dysmorphologist?
A. A dysmorphologist is a boarded pediatrician (American Board of Pediatrics) who has spent two to three additional years in training focusing on the causes, treatment and prevention of birth defects. Dysmorphology is a system for the approach to clinical diagnosis in the areas of birth defects and developmental abnormalities. Most physicians who specifically call themselves dysmorphologists either trained with Dr. Smith or with someone trained with him in order to learn this approach.
Q. What is clinical genetics?
A. Clinical genetics is a specialty in medicine recognized through board certification (American Board of Medical Genetics). The focus of clinical genetics is on identifying the genetic contribution to health and disease across the broad field of medicine.
Q. What kind of a physician is a clinical geneticist?
A. Although clinical genetics may be entered as a primary residency straight out of medical school, the vast majority of practitioners obtain certification in a primary specialty first (pediatrics, internal medicine, family medicine, obstetrics and gynecology) before entering a two- to three-year residency in genetics. The focus of training is on the evaluation of individuals with genetically determined problems and the assessment of genetic and reproductive risk for health and disease. Geneticists think of diagnoses in the context of the family in which the problem has occurred. Often the patient presenting for evaluation is not the only member of the family needing information.
Q. What is the difference between dysmorphology and clinical genetics?
A. There is a great deal of overlap; however, dysmorphology is the study of birth defects and developmental abnormalities. Although some have a genetic cause, many do not. Dysmorphology looks at the problem of birth defects in the widest possible construct. Clinical genetics involves the study of the impact of altered genes on health and disease. Although many developmental syndromes have been documented to have a genetic cause, some genetic abnormalities (such as those causing predisposition to cancer) have nothing to do with birth defects. The two fields overlap but are not synonymous.
Q. What will happen during the visit?
A. Most of the initial visit will involve taking a family history, collecting information about the pregnancy and delivery of the person being evaluated, discussing past evaluations (bring records if you have them), and performing a detailed physical examination assessing differences in structure. None of the primary evaluation should be frightening or painful to a child. If further laboratory testing is necessary, a decision can usually be made at that time if further appointments will be necessary or if follow up can be accomplished through a telephone conversation. In some instances an individual will need sequential evaluation to clarify a diagnosis.
Q. What is a family history?
A. A family history is the story of one’s genetic origins. Family histories can provide important clues to the cause of a problem or to the type of testing that should be considered. The taking of a family history involves questions about the health/developmental status of parents, siblings, their offspring and distant relatives, whether they are living or dead. It involves information about miscarriages and early deaths. It involves questions about ethnicity and family origin.
During the evaluation, we will construct a family tree. There are two major reasons why this information is important. For the dysmorphologist, alterations in form are significant only if they are unusual for a particular family. Understanding an individual’s genetic background may help interpret certain physical differences. For example, a low nasal bridge would be unusual in a 10-year-old boy whose parents were both of Scandinavian origin. This finding might be completely normal in a 10-year-old boy whose parents were both from the Philippines. If structural differences are a concern, bring family pictures to the appointment. For the clinical geneticist, knowledge of genetic background is helpful in determining whether or not a genetic contribution to the problem in question should be considered. For example, a microcytic anemia in a child of mixed Northern European descent is likely to represent iron deficiency. A similar problem in a Vietnamese child could suggest a form of thalassemia.
We recognize that issues of genetic background often fly in the face of true family relationships. For example, adoptive parents are clearly the parents of a child; however, they are not the source of the genes. Stepparents may have raised a child; however, they may not be the source of the genes. If questions about biological relationships may be uncomfortable to discuss in front of a child, please let us know and we will be happy to structure another forum to obtain the information if it is necessary. Not all families know information about genetic origins, which may be distinct from geographic origins. For example, an individual describing his/herself as “Mexican“ could be Olmec, Mayan, Aztec or descended from other indigenous groups, Spanish, French, or a mix of the three. An individual from “Texas” could be Native American, Spanish, mestizo, African American, mixed European or a combination of the above, each group having its own specific disease risks.
Ethnicity and race have become polarizing issues in society because of eugenic, political, and cultural concerns. The dysmorphology and genetics division respects the diversity and richness of the human population and asks questions about ancestry in the context of genetic diagnosis. If you do not know your family history and someone is alive who could share the information with you, consider contacting him/her. As stated above, family photographs may be invaluable in discerning family resemblance.
Q. My doctor has suggested that my child might have a specific diagnosis. Should I investigate on the Internet?
A. It is important to recognize that a significant proportion of patients referred to rule out “condition X” by a primary physician, does not have the disorder. The primary care physician is merely being thorough in his/her evaluation in making the referral. The Internet has lots of useful information; however, none of it is interpreted or filtered. The family page information and the support group information tend to depict the most severe end of the spectrum of the diagnosis. Those who are doing very well often have little need to network with others. Our only advice is know yourself. If you can process information without feeling as though everything that you are reading about might happen to your child, by all means search. If lots of information has a tendency to frighten and overwhelm you, we suggest that you wait until the appointment. If the diagnosis is confirmed, we can and will suggest appropriate (and accurate) sites for you. If the diagnosis is not confirmed, then you have not worried needlessly.