Human genetics is a specialist field of medicine and encompasses the education, detection and treatment of genetic diseases in humans, including genetic counselling for patients and their families as well as doctors working in healthcare.
Human genetic counselling
Who is eligible for genetic counselling?
Families or individuals can turn to the genetic counselling centre if:
- you yourself are affected by a hereditary disease (diseases from all medical specialities) or suspect such a disease
- a child was born with a probable or certain hereditary disease or malformation
- if hereditary diseases have occurred or are suspected in close relatives,
- the partners are related
- you want to find out about the age-related risk and/or prenatal diagnosis during pregnancy
- have been affected by external factors (infections, radiation, medication, chemicals) before or during pregnancy, or you have a chronic illness
- have had repeated miscarriages
- couples are planning to undergo artificial insemination due to an unfulfilled desire to have children
- there is a suspicion of genetic growth disorders in you or your child
Materials required
- the medical documents and findings of the patient available to date
- the patient’s x-rays (if relevant for clarifying the issue)
- the exact address of the attending physician or hospital
- the maternity record
- the children’s yellow examination booklets
Cost unit
The costs of genetic counselling are usually covered by health insurance companies. Patients with health insurance must present a referral slip and their insurance card.
For privately insured patients, we are happy to provide a cost estimate based on the scale of fees for doctors (GOÄ). Please contact us informally at info@genetik-dresden.de. We also ask privately insured patients to send us the completed request form to commission genetic tests.
Contact
To make an appointment, you can contact your practice directly in writing, by telephone or using the online form.
Aim of prenatal diagnostics
The aim of prenatal diagnostics is to
- to recognise disorders of embryonic and foetal development,
- to objectify and reduce any fears and concerns the pregnant woman may have,
- to enable optimal treatment for the child through early detection of malformations and diseases and
- to help pregnant women decide whether to continue or terminate the pregnancy.
A prenatal finding alone does not justify a termination of pregnancy. It can lead to an ethical conflict between the parents’ desire for a healthy child and recognising the unborn child’s need for protection.
Information and counselling for pregnant women
Before prenatal diagnostics, detailed counselling must be provided about
- Reason for the examination
- The aim of the examination
- Limits of the diagnostic possibilities
- Certainty of the examination results
- Type and severity of the suspected disorder
- Options for dealing with pathological findings
- Psychological and ethical potential for conflict in the presence of pathological findings
- Alternatives if invasive prenatal diagnostics are not utilised
The following information should be providedafter a prenatal diagnosis:
- Significance of the findings
- Prognosis of the child’s condition
- Pre- and postnatal therapy and support options
- Consequences for birth management
- Alternative behaviour: Continuation or termination of the pregnancy
- Contact options for similarly affected people
A genetic finding is communicated by the treating or counselling doctor. The decision of the pregnant woman and the contents of the counselling session must be documented by the doctor.
Scope of prenatal diagnostics
Early detection of risk factors:
- from the patient’s own medical history (e.g. diabetes mellitus, cerebral seizure disorders, autoimmune disease)
- from family and pregnancy history (miscarriages, stillbirths, malformations, genetic diseases)
- from ethnic origin (e.g. β-thalassaemia risk, intermarriage)
- Exposure to mutagenic, teratogenic or foetotoxic agents
- Ingestion or abuse of medication, stimulants, drugs, etc.
Risk assessment
- Human genetic counselling is recommended for every genetic risk, as required by the maternity guidelines.
- If exposure to mutagenic, teratogenic or foetotoxic noxious substances is suspected, expert information should be obtained from a human geneticist, pharmacologist, toxicologist, radiation biologist or the Embryo Toxicological Counselling Service. the risk of such noxious substances is usually overestimated. Only in the case of some toxins, e.g. the intake of valproic acid, is an invasive diagnosis indicated. A detailed ultrasound diagnosis is necessary for confirmation.
- If foetotoxic infectious agents are suspected, further examinations by microbiologists are necessary (e.g. toxoplasmosis, rubella, varicella, rubella and borreliosis).
Risk specification using sonographic and biochemical markers
Please refer to the detailed expert reports on first trimester screening.
Possible reasons for targeted invasive prenatal diagnostics
- Increased risk of chromosomal aberration due to increased maternal age. The risk figures for a de novo chromosomal aberration depend on the time of collection of the foetal material. For this reason, different risk figures are given for chorionic villus material (in the 11th to 13th week of pregnancy), after amniotic cell cultivation (in the 16th week of pregnancy) and in the newborn (see Appendix; Tables 1 – 3).
- Structural or numerical chromosomal aberration in one parent or condition after birth of a child with a chromosomal disorder.
- Abnormal serum markers, especially if the individual risk is greater than that of a 35-year-old pregnant woman.
- Diseases that can be diagnosed prenatally using molecular genetic diagnostics. In many cases, it is necessary to use the DNA findings of the index case and the parents.
- Suspicious sonographic findings
- Ultrasound findings with a higher risk of a chromosomal disorder
- Growth retardation of ≥ 4 weeks or rapid increase in the discrepancy between the calculated gestational age and the gestational age determined by ultrasound
- Hygroma colli
- Gastrointestinal obstruction (duodenal atresia)
- Polycystic kidneys (with an empty family history)
- Genital malformations
- Ultrasound findings with a lower risk of a chromosomal disorder
- Growth retardation
- Micro- and macrocephalus
- Brain malformations
- Neural tube defect
- Facial clefts
- Heart defects
- Malformations of the kidneys and/or urinary tract
- Malformations of the extremities
- Oligohydramnios or hydramnios
- Non-immunological hydrops fetalis
There is a dependence on the isolated or combined occurrence of the sonographic findings for the occurrence of foetal chromosomal abnormalities (see Appendix; Table 4).
- Ultrasound findings with a higher risk of a chromosomal disorder
Methods of fetal material collection
- Amniocentesis (AZ; amniotic fluid puncture)
- Chorionic villus sampling (CVS) / placental biopsy
- Cordocentesis
Organ biopsy e.g. skin, liver, muscle and embryofetoscopy are obsolete procedures.
The cytogenetic result is available at:
- CVS short-term culture after 1-3 days and has the significance of a preliminary result
- Long-term culture (CVS and amniotic fluid) after 10 – 21 days
- Umbilical cord puncture after 3 – 5 days
Interphase FISH diagnostics and/or rapid molecular genetic diagnostics are used to detect the most common aneuploidies, but cannot replace karyotyping.
Abortion risks of invasive diagnostics
| Amniocentesis: | approx. 0.5 % |
| Chorionic villus sampling: | approx. 1.0 % |
| Fetoscopy with skin biopsy: | > 3.0 % |
Ethical and legal aspects
Prenatal diagnostics are useful and medically advisable if they can treat a disease intrauterine or ensure timely postnatal therapy.
If treatment is not possible, the only decision that can be made is whether to continue or terminate the pregnancy. If a decision is made in favour of abortion, all parties involved come into conflict with the prohibition of killing. Abortion is an imperfect endeavour to end a conflict situation that cannot be resolved in essence.
According to Section 218, the diagnosis of a serious illness of the child can be a prerequisite for the unreasonableness of continuing the pregnancy.
An abortion is not unlawful “if it is necessary, taking into account the present and future living conditions, to avert danger to life or the risk of serious impairment of the physical or mental health of the pregnant woman” (Section 218 a, para. 2, StGB).
The doctor and patient enter into a treatment contract. This obliges the doctor to diagnose damage to the foetus. If the doctor fails to take justified diagnostic measures, he is in breach of the treatment contract and may be liable for damages. A landmark judgement on the risk of genetic counselling states: “In the case of incorrect genetic counselling that has led to the birth of a genetically handicapped child, the parents can demand full compensation for the child’s maintenance needs from the counselling doctor if they would not have conceived the child if they had received correct and complete counselling.”
(BGB § 828 Aa, § 249 A, GG Art.1)
Carrier Screening – Desire to have children
Just under 1% of European couples have a risk of their child developing a severe genetic, autosomal recessive disorder because the healthy parents are carriers.*¹ The combination of both parental predispositions in the child results in the disorder.
A carrier test is a genetic test for these predispositions. It determines whether there is an increased risk of a particular genetic disease occurring in the offspring of a couple (autosomal recessive inheritance) or a woman (X-linked inheritance). The aim is to enable the couple to make an informed decision in the context of family planning.
We offer carrier screening for three relatively common hereditary diseases. Cystic fibrosis and spinal muscular atrophy are the first two diseases for which pan-ethnic screening*² was offered in English-speaking countries.
Cystic fibrosis
Cystic fibrosis (CF, mucoviscidosis) is one of the most common autosomal recessive inherited diseases in Central Europe. The classic form is a multi-system disease, including the lungs and pancreas. Without treatment, the disease is life-shortening. The frequency of carriers in the population, the so-called heterozygote frequency, is 1:25 in Northern Europe.
Spinal muscular atrophy
Spinal muscular atrophy (5q- or SMN1-associated) is a common autosomal recessive inherited neuromuscular disease. In the most severe form, children die in the first few months of life as a result of muscle weakness with respiratory insufficiency. Causal therapeutic approaches are now available. The heterozygote frequency is 1:35 in Northern Europe.
Fragile X syndrome
Fragile X syndrome is the most common cause of inherited intellectual disability in boys. It is estimated that 1 in 259 women are conductors*³ for this disorder with X-linked inheritance.
Are you interested in carrier screening? We will be happy to inform you in our genetic consultation hours and discuss with you, taking into account your family history and your need for safety, which diseases or carriers we should examine. Carrier screening requires genetic counselling. As a rule, this is a self-pay service (in the case of an unremarkable family history with regard to the above-mentioned diseases).
*¹Fridman et al. 2021, https://doi.org/10.1016/j.ajhg.2021.03.004
*² Early detection examination regardless of the ethnic origin of the couple
*³ healthy woman who carries a hereditary disease predisposition on one of the two X chromosomes
