Biology Reference
In-Depth Information
TABLE 9.1. The genetic counseling process
1. Collection of family history
2. Collection of medical history
3. Review of audiometric information
4. Physical examination by certified clinical geneticist
5. Additional medical studies or referral to specialists
6. Screening for genes for deafness/referral to research protocols
7. Discussion of diagnosis, inheritance pattern, prognosis and treatment options
8. Follow-up and other referrals
3.1 Family History
Family history information is critical in making a diagnosis of the cause of
deafness. The mode of inheritance of the hearing loss or clues to the pres-
ence of a syndromic form of deafness is often revealed through the careful
collection of an accurate family history. Important information includes
the health and hearing status of siblings, parents and other close family
members, the possible occurrence of consanguinity (blood relationship)
between the parents of a child with hearing loss, and ethnic background.
Questions that reveal possible syndromic forms of deafness focus on the
occurrence of eye disease; pigmentary changes of the skin, hair, or eyes;
structural malformation of the ears or face; skeletal variations; and other
problems such as kidney malformations or heart disease (Griffith and
Friedman, Chapter 6).
3.2 Medical History
A medical history profile can be assembled by obtaining copies of records
documenting birth history, chronic health problems, or other serious ill-
nesses that may be related to the etiology of the hearing loss. Medical infor-
mation may be collected on other family members as well as the person or
persons with hearing loss. Such information provides useful details about a
possible syndromic form of deafness in the family or may assist in ruling
out environmental (nongenetic) causes of the hearing loss.
3.3 Audiologic History
Information regarding age of onset, and degree and severity of hearing
loss is typically collected for all family members by the genetic counselor
through the interview process. Subsequent documentation of these para-
meters of hearing loss may be obtained by requesting copies of previous
evaluations, or asking family members to have a comprehensive evaluation
by a certified audiologist.
