Carmella S. Stadter
Genetic counseling, defined as the provision of medical, prognostic, and recurrence risk information about a disorder together with psychosocial support to the family, can be a complex undertaking when dealing with oral clefting. Previous chapters have dealt with medical and prognostic counseling, and this chapter will concentrate on recurrence risk and supportive counseling. Patients and families need to be made aware of their recurrence risks and reproductive options in an easy to understand manner with attention paid to the emotional impact of the information. Counseling an individual with a physical defect of the face, one of the most obvious and public parts of the body, is challenging. As with genetic counseling for any condition, one of the key aspects of supportive counseling for families with oral clefts is listening and allowing them to voice their concerns, frustrations, and joys. As discussed in earlier chapters, cleft lip with or withoutcleft palate (CL/P) and cleft palate alone (CP) result from distinctly different developmental processes occurring at different gestational ages. While these differences lead to certain counseling issues unique to each condition, there are also a number of important counseling issues shared by both conditions.
Recurrence Risks
A thorough physical examination of the patient and other family members and a careful medical and family history are of utmost importance to the accuracy of recurrence risk counseling. These tools help to establish the etiology of the cleft, whether the cleft is an isolated abnormality or part of a multiple malformation syndrome in the patient, and whether there is any familial clustering of oral clefts. Only after establishing the etiology can thorough, accurate, and relevant genetic counseling be provided to the patient and family.
Isolated Oral Clefts
Oral clefts are most often isolated, meaning that they are primary defects with no other associated abnormalities or syndromic features. Among oral clefts, CP is more likely to have associated abnormalities and syndromes than CL/P. Isolated oral clefts have long been assumed to be inherited in a multifactorial manner, meaning that numerous genes in combination with environmental factors contribute to the formation of the cleft. This model assumes a threshold effect in which there is a critical mass of contributory genetic and environmental factors that need to be reached before an oral cleft occurs. Recent studies have questioned the applicability of the multifactorial model to all clefts and have proposed instead a greater degree of heterogeneity than previously thought, with at least some familial oral clefts being the result of the presence of one, or at the most a few, major predisposition genes with incomplete penetrance (Jones, 1993; Carinci et al.,2000). Issues surrounding the genetic mechanisms of isolated oral clefts are explored in much greater detail elsewhere in this book (see Part IV).
While theoretically it is likely that there is heterogeneity among isolated oral clefts, with some families segregating a major predisposition gene with incomplete penetrance, practical genetic counseling for the isolated cleft still relies on data of incidence recurrence within a family compiled over years. If after thorough evaluation, including a physical examination by an experienced clinical geneticist and a careful family history, the patient is diagnosed with an isolated oral cleft, the family should be provided information on recurrence risks based on empiric data (Table 31.1). In general, the risk increases with the number of affected family members, so it is important to examine other family members for subtle or subclinical oral clefts. Additionally, recurrence risks tend to increase with increasing severity of the oral cleft, so the higher end of the risk figure range may be more appropriate in the case of a bilateral vs. a unilateral oral cleft in the proband (Lynch and Kimberling, 1981; Robinson and Linden, 1993; Wyszynski et al., 1996; Harper, 1999). Bixler (1981) found a much reduced recurrence risk (<1%) when the cleft was sporadic vs. an increased risk (16%) when there was a history of clefting in a firstor second-degree relative.
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TABLE 31.1. Recurrence Risks for Isolated Oral Clefts |
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However, these risks are most appropriately applied to cases of oral clefts in which no, or only an occasional, family member is affected. If the family history shows a number of members affected with oral clefts or other associated abnormalities, then a clefting syndrome or the possibility of mendelian inheritance (e.g., autosomal dominant with decreased penetrance) should be considered. A higher recurrence risk figure based on these findings may be appropriate.
Syndromic Oral Clefts
In approximately 35% to 50% of cases CP and 7% to 15% of cases CL/P, other physical abnormalities are seen in the affected individual (Jones, 1993; Robinson and Linden, 1993). The presence of any other birth defect or health concern should prompt an evaluation by a clinical geneticist, looking for evidence of an underlying genetic syndrome. There are well over 200 known syndromes featuring oral clefts, with etiologies including single-gene defects, teratogens, chromosomal abnormalities, and those with uncertain etiology. The more common and relevant of these conditions are discussed in Part II of this book. However, additional abnormalities that may be seen in a child with a cleft are not automatically assumed to be due to an underlying syndrome. Any associated abnormalities may be due to the same disruptive event as the cleft itself and, therefore, may constitute an association rather than a syndrome.
If a specific syndrome is identified, the recurrence risk is that of the syndrome itself. Of special note are syndromes caused by teratogens, such as fetal alcohol syndrome. The recurrence risk of the syndrome, and thus the oral cleft, should be neglible if the teratogen is removed in future pregnancies. If no specific syndrome is recognized in a child but suspicion of a genetic condition is high based on associated abnormalities, a worst-case scenario recurrence risk of up to 25% for unaffected parents (assuming autosomal recessive inheritance) should be discussed.
Recurrence Risk Reduction
There is a possible decrease in recurrence risks for oral clefts in women taking supplemental folic acid, similar to the situation with open neural tube defects (Hartridge et al., 1999; Mills, 1999). This is most applicable to couples facing the recurrence risk of an isolated cleft. The relationship between folic acid supplementation and oral clefting has not yet been proven and is further discussed in Part III of this book. Alternative reproductive technologies, such as the use of donor egg or sperm, may be options for couples facing a significant recurrence risk of an oral cleft as part of a genetic syndrome. As noted above, for couples facing a recurrence risk based on an oral cleft resulting from a teratogenic exposure, removal of the teratogen, if possible, from the pregnancy environment should remove the risk. Finally, prenatal diagnosis is possible in some cases and can provide parents with valuable information prior to the baby's birth.
Prenatal Diagnosis
Prenatal diagnosis of an oral cleft has been reported using visualization of the fetal facial structures by ultrasound. The accuracy of this diagnosis is highly dependent on many factors, including maternal body habitus, fetal positioning, quality of the ultrasound machine, and skill of the examiner. In general, oral clefts cannot be identified until the second trimester of pregnancy, with CL/P being easier to detect than CP. Use of three-dimensional ultrasound has increased the accuracy of prenatal diagnosis of oral clefts (Jones, 1993; Cockell and Lees, 2000). Prenatal identification of an oral cleft should prompt a careful ultrasound evaluation looking for any associated physical abnormalities that could lead to the diagnosis of a syndrome in a previously low-risk pregnancy. Fetal karyotyping should also be considered, especially in the presence of any additional anomalies.
If the oral cleft in a family is part of a recognized syndrome, prenatal diagnosis for the specific condition may be possible irrespective of the ability to visualize the cleft itself. Known chromosomal abnormalities as well as some single-gene disorders can be diagnosed prenatally by chorionic villus sampling or amniocentesis. Because clinical genetic testing changes so rapidly, the availability of prenatal testing for any given condition should be investigated on a case-by-case basis.
Supportive Counseling
Emotional support for patients with oral clefts and their families is one of the most important responsibilities of healthcare providers and is ideally provided as a group effort from all members of a craniofacial team, including a genetic counselor. The birth of a child with any type of health problem or physical abnormality can bring on a grieving process in parents. These parents grieve the loss of the “perfect” child they have visualized for 9 months (or longer) while learning to accept the fact that such a rare event as a birth defect has affected their family. As parents go through the stages of grieving, it is important to follow them and make sure they are able to navigate these stages, ideally ending up in acceptance of their child with an oral cleft. Recognition of a family unable to work through these steps and of our limitations in helping them is crucial. A genetic counselor or other craniofacial team member should not hesitate to refer a family to formal therapy if any concerns about their ability to cope arise.
It is also important to remember that each family brings to the counseling session a unique history of experiences that will mold his or her view of the present situation. Often, oral clefts are viewed as merely structural defects that are easily amenable to surgery. Fortunately, this is true for the majority of patients, but it is important not to assume that this is the experience of every patient and family. Is this the first person in the family with an oral cleft, or are there other affected members? Does one of the parents have an oral cleft? Is the oral cleft thought to be isolated in the child, or are there other health concerns and the possibility of a genetic syndrome? Is this a syndrome that has been inherited in the family? Taking the time to listen to a family and learn enough about their experiences to understand their reactions is an invaluable aid in providing useful supportive counseling.
Isolated Oral Clefts
The many medical issues surrounding the birth of a child with an oral cleft can often leave a family feeling overwhelmed. Consultation with a comprehensive craniofacial/oral cleft clinic team can be invaluable to help the parents learn how to manage the medical needs of their child. The type and severity of the oral cleft, especially in terms of its impact on feeding, also greatly affect the amount of support and counseling a family may need. Early contact with a family reassures them that they are not alone and that there experienced people available to help them care for their child. This “safety net” of healthcare providers will hopefully free parents from some of their worries, allowing them to channel their energies into coping with the emotional aspects of having a child with an oral cleft.
Having other members of the family with oral clefts can be a double-edged sword in regard to how it may impact on a family's reaction. The way in which a family reacts depends greatly on the experience of the other affected family members. If a previous individual with a cleft had a successful repair with few or no complications, this will obviously help allay many of the fears a family may have. However, a previous member with a poor repair experience may make a family even more frightened of the future. This is especially true of a parent who had a cleft as a child; it is likely that surgical repair was not as good then, so it is not uncommon to encounter a parent with bad memories of the experience. Because the face is the first thing noticed about a person, a less-than-optimal repair can lead to emotional problems, from internal and external sources, especially during adolescence. Envisioning their children going through a similar experience can be very upsetting for parents, and they may be greatly reassured when recent advances in surgical repair are discussed. Finally, the birth of a second child with a cleft forces parents to relive the grieving process and increases their anxiety and risks of having another child with an oral cleft.
Syndromic Oral Clefts
Another important consideration is whether the oral cleft is associated with other health concerns, possibly a recognized syndromic condition. This will have a great impact on how much time and energy the child will spend in hospitals having surgeries and seeing doctors. This will also greatly affect how the parents view their child's oral cleft in that the oral cleft is not the only health problem their child faces. For some families, an oral cleft may be the least of their concerns compared to the other, possibly life-threatening features of the syndrome and severe developmental disabilities. What may have been an emotionally devastating birth defect if isolated may now be viewed as simply a surgically repairable health concern.
The parents of a child with a syndromic oral cleft face all of the emotional issues faced by the family of a child with an isolated oral cleft in addition to those concerning the syndrome. The risk of developmental delay or mental retardation in a child with a syndromic cleft is a significant concern (Kapp-Simon and Krueckeberg, 2000). The presence of mental retardation is one of the most emotionally burdensome aspects of dealing with a syndromic condition. Another consideration is the special instance of a mildly affected parent who is diagnosed with a genetic syndrome after the more severely affected child is born. In this situation, a parent deals with his or her own diagnosis as well as the diagnosis of the child. Thus, families of children with a syndromic oral cleft may warrant closer attention as they cope with the diagnosis of a syndrome as well as the oral cleft and all of the consequences that the diagnosis may hold for the child.
Guilt
Having a child with an oral cleft brings guilt feelings to any parent at having possibly caused the cleft. In the absence of a known teratogen, parents should be reassured that nothing either of them did before or during the pregnancy caused oral cleft. Also, no one has any control over the genes they pass on to a child, whether the oral cleft is isolated or part of a recognized syndrome. This becomes an especially emotionally charged issue if one of the parents also has an oral cleft. Again, special attention should be paid to the issue of guilt as it often persists, even when the parents intellectually understand that they had no control over the situation.
For those cases in which the oral cleft is thought to be the result of a teratogen, there will likely always be guilt and remorse on the part of the parents over the use of the medication or drug during pregnancy. If the teratogen, as in the case of antiepileptic medication, carries a definite benefit to the mother despite the risk of oral clefting in the fetus, this benefit and the possible negative ramifications of discontinuing the medication during the pregnancy can be stressed. In cases of teratogens without known benefit, such as alcohol, counseling should stress education of the cause and effect of the teratogen and the benefits of avoiding the exposure in future pregnancies.
Peer Support Groups
Support from healthcare providers can be very valuable to families, especially in the first days and weeks of a child's diagnosis; however, an even more worthwhile source of support is other families of children with an oral cleft. Though we, as healthcare providers, can discuss the medical and psychosocial aspects of having a child with an oral cleft, other families in similar situations are the true experts on the day-to-day realities of raising a child with a cleft. It is also very valuable for children as they grow into adolescence and adulthood to have peers to talk with about problems they face that may be unique to a child with an oral cleft. National support groups geared toward families affected by oral clefting are listed in the Appendix to this book.
These are some of the more important issues that come up when providing genetic counseling for families of a child with an oral cleft. Each family is unique and will teach the healthcare provider a new aspect of coping with a child born with an oral cleft. Our job as providers of genetic counseling is to remain open and to actively listen to families so that we are able to best address their needs with any resources we may have. This is the way in which we continue to learn so that, hopefully, each new family can benefit from our past experience as well as the experiences of previous families.
References
Bixler, D (1981). Genetics and clefting. Cleft Palate J 18: 10–18.
Carinci, F, Pezzetti, F, Scapoli, L, et al. (2000). Genetics of nonsyndromic cleft lip and palate: a review of international studies and data regarding the Italian population. Cleft Palate Craniofac J 37: 33–40.
Cockell, A, Lees, M (2000). Prenatal diagnosis and management of orofacial clefts. Prenat Diagn 20: 149–151.
Harper, P (1999). Practical Genetic Counseling. Boston: Butterworth-Heineman, pp. 210–212.
Hartridge, T, Illing, H, Sandy, J (1999). The role of folk acid in oral clefting. Br J Orthod 26: 115–120.
Jones, M (1993). Facial clefting etiology and developmental pathogenesis. Clin Plast Surg 20: 599–606.
Kapp-Simon, K, Krueckeberg, S (2000). Mental development in infants with cleft lip and/or palate. Cleft Palate Craniofac J 37: 65–70.
Lynch, H, Kimberling, W (1981). Genetic counseling in cleft lip and cleft palate. Plast Reconstr Surg 68: 800–815.
Mills, J (1999). Folate and oral clefts: where do we go from here? New directions in oral clefts research. Teratology 60: 251–252.
Robinson, A, Linden, M (1993). Clinical Genetics Handbook. Oxford: Blackwell, pp. 515–521.
Wyszynski, DF, Beaty, TH, Maestri, N (1996). Genetics of nonsyndromic oral clefts revisited. Cleft Palate Craniofac J 33: 406–417.