KRONİK HASTALIĞI OLAN ÇOCUKTA GENETİK DANIŞMANLIK


Karaman B., Gedikbaşı A.

in: Kronik hastalığı olan çocuğun izlemi ve toplumda bakım, Gülbin Gökçay,Gonca Keskindemirci, Editor, Istanbul University Press, İstanbul, pp.715-733, 2024

  • Publication Type: Book Chapter / Chapter Vocational Book
  • Publication Date: 2024
  • Publisher: Istanbul University Press
  • City: İstanbul
  • Page Numbers: pp.715-733
  • Editors: Gülbin Gökçay,Gonca Keskindemirci, Editor
  • Istanbul University Affiliated: Yes

Abstract

Genetic diseases result in chronic illnesses, progressive disability, and in some cases, premature death. The increase in the use of genetic screening and diagnostic technologies has resulted in a higher number of applications for hospitalization based on the knowledge about genetic diseases. Basic genetic counseling has become more important in primary health care. In order to identify individuals or families in the high-risk group, guide them correctly, and give adequate answers to their questions, physicians who encounter such patients should have sufficient and accurate knowledge. Genetic counseling is the process of informing the families of children with a hereditary disease or at risk of carrying it, about the course of the disease, the risks of recurrence, the treatment, and appropriate tests and their results. Moreover, genetic counseling is defined as the communication process between the family and the consultant on issues such as medical facts, the contribution of heredity to real life, the evaluation of the genetic test results, and the possibilities associated with them. Genetic counseling is the most important tool to prevent genetic diseases and is effective in protecting individual, family, and public health in terms of genetics. In the pediatric age group, conditions requiring genetic counseling include abnormal newborn screening results, recognizable genetic syndromes such as trisomy 21, congenital anomalies, gender development disorders, vision or hearing problems, mental or developmental disabilities, and autism spectrum disorders. During genetic counseling, a detailed family history should be taken and a family tree should be drawn in which the pedigree should include at least three generations and family members with similar characteristics are specified. Thus, possible risks are also reviewed among all family members. If present, those who have evidence of the disease and other family members should be further examined by chromosome analysis, DNA analysis, and enzyme tests . Undiagnosed patients are followed up, but no information can be drawn about the risks of recurrence. Disease-specific genetic counseling should be provided in patients with multiple congenital anomalies and intellectual disabilities (MCA-ID) caused by numerical and structural abnormalities of chromosomes and in those with known syndromes such as trisomy 21, Turner syndrome, Klinefelter syndrome, or Noonan syndrome. Inheritance patterns may hint disease transmission among generations of a family. An autosomal pattern of inheritance occurs in families affected with a genetic disease whose gene is not on a sex chromosome, for example, when the parents are each carrier with the another term heterozygous. Therefore, with the mating of carrier parents, there is a 25% chance that the child will be affected, a 50% chance that the child would be a carrier, and 25% chance that they would be unaffected non-carrier. Consanguineous marriage is an important problem that requires genetic counseling, especially in terms of autosomal recessive diseases in which the parents are carriers and do not show signs of the disease. Notably, several rare genetic disorders are due to autosomal recessive inheritance. Meanwhile, cystic fibrosis, phenylketonuria, spinal muscular atrophy, congenital adrenal hyperplasia, thalassemia, and sickle cell anemia are screened by national screening programs in Turkey. Thus, it is important to know the general principles of genetic counseling. In multifactorial diseases such as neural tube defects and cleft palate and lip, the risk of disease-specific recurrence should be determined during genetic counseling. In conclusion, even general practitioners should receive additional training for genetics in order to provide effective genetic counseling. Overall, there is clearly an urgent need to establish eligibility criteria for genetic counseling providers.