RESUMEN
Updated from their original publication in 2004, these cancer genetic counseling recommendations describe the medical, psychosocial, and ethical ramifications of counseling at-risk individuals through genetic cancer risk assessment with or without genetic testing. They were developed by members of the Practice Issues Subcommittee of the National Society of Genetic Counselors Familial Cancer Risk Counseling Special Interest Group. The information contained in this document is derived from extensive review of the current literature on cancer genetic risk assessment and counseling as well as the personal expertise of genetic counselors specializing in cancer genetics. The recommendations are intended to provide information about the process of genetic counseling and risk assessment for hereditary cancer disorders rather than specific information about individual syndromes. Essential components include the intake, cancer risk assessment, genetic testing for an inherited cancer syndrome, informed consent, disclosure of genetic test results, and psychosocial assessment. These recommendations should not be construed as dictating an exclusive course of management, nor does use of such recommendations guarantee a particular outcome. These recommendations do not displace a health care provider's professional judgment based on the clinical circumstances of a client.
Asunto(s)
Asesoramiento Genético , Pruebas Genéticas , Neoplasias/genética , Medición de Riesgo , Predisposición Genética a la Enfermedad , Humanos , Recursos HumanosRESUMEN
In 1994, the molecular basis of pachyonychia congenita (PC) was elucidated. Four keratin genes are associated with the major subtypes of PC: K6a or K16 defects cause PC-1; and mutations in K6b or K17 cause PC-2. Mutations in keratins, the epithelial-specific intermediate filament proteins, result in aberrant cytoskeletal networks which present clinically as a variety of epithelial fragility phenotypes. To date, mutations in 20 keratin genes are associated with human disorders. Here, we review the genetic basis of PC and report 30 new PC mutations. Of these, 25 mutations were found in PC-1 families and five mutations were identified in PC-2 kindreds. All mutations identified were heterozygous amino acid substitutions or small in-frame deletion mutations with the exception of an unusual mutation in a sporadic case of PC-1. The latter carried a 117 bp duplication resulting in a 39 amino acid insertion in the 2B domain of K6a. Also of note was mutation L388P in K17, which is the first genetic defect identified in the helix termination motif of this protein. Understanding the genetic basis of these disorders allows better counseling for patients and paves the way for therapy development.
Asunto(s)
Displasia Ectodérmica/genética , Queratinas/genética , Queratodermia Palmoplantar/genética , Uñas Malformadas/genética , Secuencia de Bases , ADN/genética , Análisis Mutacional de ADN , Enfermedad de Darier/congénito , Enfermedad de Darier/genética , Femenino , Humanos , Queratodermia Palmoplantar/congénito , Masculino , Mutación , Uñas Malformadas/congénito , Linaje , FenotipoRESUMEN
These cancer genetic counseling recommendations describe the medical, psychosocial, and ethical ramifications of identifying at-risk individuals through cancer risk assessment with or without genetic testing. They were developed by members of the Practice Issues Subcommittee of the National Society of Genetic Counselors Cancer Genetic Counseling Special Interest Group. The information contained in this document is derived from extensive review of the current literature on cancer genetic risk assessment and counseling as well as the personal expertise of genetic counselors specializing in cancer genetics. The recommendations are intended to provide information about the process of genetic counseling and risk assessment for hereditary cancer disorders rather than specific information about individual syndromes. Key components include the intake (medical and family histories), psychosocial assessment (assessment of risk perception), cancer risk assessment (determination and communication of risk), molecular testing for hereditary cancer syndromes (regulations, informed consent, and counseling process), and follow-up considerations. These recommendations should not be construed as dictating an exclusive course of management, nor does use of such recommendations guarantee a particular outcome. These recommendations do not displace a health care provider's professional judgment based on the clinical circumstances of a client.
