• Like
  • Save
Genetic counselling
Upcoming SlideShare
Loading in...5
×
 

Genetic counselling

on

  • 3,318 views

 

Statistics

Views

Total Views
3,318
Views on SlideShare
3,318
Embed Views
0

Actions

Likes
1
Downloads
149
Comments
2

0 Embeds 0

No embeds

Accessibility

Categories

Upload Details

Uploaded via as Microsoft PowerPoint

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel

12 of 2

  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Processing…
Post Comment
Edit your comment

    Genetic counselling Genetic counselling Presentation Transcript

    • GENES Genes are the units of heredity. They affect development and function, both normal and abnormal.
    • They are of 3 types:1.Chromosomal abnormalities2.Mendelian diseases3.Multifactorial disorders
    • 1.CHROMOSOMAL ABNORMALITIES A.Klinefilter syndrome B.Turners syndrome.2.MENDELIAN DISEASES A.Dominant B.Recessive C.Sex linked diseases
    • 3.MULTIFACTORIAL DISORDERS A.Hypertension B.Schizophrenia C.Diabetes D.Congenital heart disease
    • 1.HEALTH PROMOTIONAL MEASURES: A.EUGENICS: a.Negative eugenics: AIM:To reduce the frequency of hereditary disease and disability in the community to as low as possible
    • B.POSITIVE EUGENICS: AIM:To improve the genetic composition of the population by encouraging carriers of desirable genotypes.
    • B.EUTHENICS : Studies with mentally retarded childrenindicated that exposure to environmentalstimulation improved their IQ.This environmental manipulation is calledeuthenics.
    • They are of 2 types: 1.Prospective 2.Retrospective1. Prospective genetic counselling:This allows for the true prevention of disease.
    • This approach requiresIdentifying heterozygous individuals for any particular defect by screeningExplaining to them the risk of their having affected children if they marry another heterozygote for the same gene.
    • If heterozygous marriage can be prevented or reduced,the prospects of giving birth to affected children will diminish.EX: Sickle cell anaemia Thalassemia2. Retrospective genetic counselling: Most genetic counselling at present is retrospective,i.e,the hereditary disorder has already occurred within the family .
    • A survey carried out by the WHO showed that genetic advice was chiefly sought in connection with congenital abnormalities Mental retardation Psychiatric illnes Inborn errors of metabolism Premarital advice
    •  The WHO recommends the establishment of genetic counselling centres in sufficient numbers in regions where infectious disease and nutritional disorders have been brought under control And in areas where genetic disorders have always constituted a serious public health problem.
    • The methods which could be suggested under retrospective genetic counselling are:1. Contraception2. Pregnancy termination.3. Sterilization
    • OTHER GENETIC PREVENTIVE MEASURES1.CONSANGUINEOUS MARRIAGES: When blood relatives marry each other there is an increased risk in the offspring of traits controlled by recessive genes and those determined by polygenes.EX: Albinism, Alkaptonuria, Phenylketonuria
    • An increased risk of premature death is alsonoted in such offspring.Therefore , a lowering of consanguineousmarriages would be advantageous to thehealth of the community.
    • 2.LATE MARRIAGES: Trisomy or mongolism is more frequent in children born of elderly mothers. Hence early marriage of females is better than late marriage from the point of view of preventing mongolism.
    • SPECIFIC PROTECTION: Patients undergoing x-ray examination should be protected against unnecessary exposure of the gonads to radiation. X-ray examination of the pregnant uterus to determine the twins or the lie of the foetus is to be strongly deprecated.
    • Rh haemolytic disease of the newborn whichis a genetically determined immunologicaldisorder is now preventable by immunizationby anti D globulin.
    • EARLY DIAGNOSIS AND TREATMENT:1.DETECTION OF GENETIC CARRIERS : It is possible to identify the healthy carriers of a number of genetic disorders, especially the inborn errors of metabolism.
    • 2.PRENATAL DIAGNOSIS:INDICATIONS:- Advanced maternal age- Previous child with chromosome aberration- Intrauterine growth delay- Biochemical disorders- Congenital anomaly- Screening for neural tube defects and trisomy.
    • 3.SCREENING OF NEWBORN INFANTS:Screening tests for early diagnosis of :- chromosome abnormalities- congenital dislocation of hip- congenital hypothyroidism- sickle cell disease- cystic fibrosis
    •  Genetic counselling can have the greatest impact when individuals or couples at genetic risk are identified, before they have developed symptoms themselves or produced their first affected child.
    • REFERENCETEXT BOOK OF PREVENTIVE ANDSOCIAL MEDICINE : PARK