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Gene panels for Clinical Areas

Clinical AreaPerinatal medicine

Associated diseases

Notes on the clinical area

Here you will find the disease-related gene panels available for the clinical area specified above.

If you cannot find the disease you are looking for, please use a known synonym in the search (also in English).

Perinatal medicine

In addition to prenatal ultrasound, genetic examinations have become increasingly important in the care for pregnant women. Nowadays, a very large proportion of prenatal issues are successfully treated using non-invasive methods (see recommendations of DEGUM and the FMF-Germany).

First trimester screening

First-trimester screening consists of a combination of ultrasonographic procedures (measurement of nuchal translucency and other fetal parameters) and biochemical tests (free ß-hCG and PAPP-A). The ratio of these parameters to each other can be used to calculate a risk measure for the most common trisomies and heart defects.

NIPT

Non-invasive prenatal tests (NIPT) offer a very high degree of certainty in trisomy diagnostics for chromosomes 21, 13 and 18 as well as for the sex chromosome status. DNA fragments from placenta cells are analysed and assigned to the respective original fetal chromosomes. In this way it is possible to obtain a reliable documentation of possible chromosomal disorders of the embryo within 24 hours. The accuracy of NIPT can be limited in rare cases by genetic differences between embryoblast and trophoblast as well as by chromosomal mosaics, vanishing twin etc. Therefore, a conspicuous NIPT finding must always be confirmed by invasive diagnostics.

Invasive procedures

The invasive prenatal diagnostic procedures for clarifying genetic questions still represent a gold standard. Amniocentesis and chorionic villus sampling are the methods of choice here. Cytogenetic and molecular genetic questions can be answered diagnostically from the cells obtained (after propagation by cultivation). Depending on the ultrasound findings, the latest DNA analysis techniques such as gene panels are also used. Here, deviations from the reference genome (wild type) are to be detected in order to differentiate between neutral variants and pathogenic mutations, which are important for the physiological development and undisturbed function of all normal cells. The inheritance patterns of prenatally diagnosable diseases represent the basis of genetic counselling for expectant parents. In the last 30 years, thousands of genes have been characterised which cause such diseases or contribute to their development. For example, mutations in independent genes on different chromosomes can cause clinically indistinguishable symptom patterns ("locus heterogeneity"). On the other hand, different mutations in one and the same gene lead to clinically apparently separated disease entities ("allelic heterogeneity").

Formal genetics and etiology

Formal genetically and etiologically, the following groups of prenatal diseases can be distinguished:

  • monogenic diseases (autosomal or X-chromosomal inheritance)
  • digenic hereditary diseases, which are only manifested when mutations are simultaneously present in heterozygous state in two different genes. Physiologically the two normal gene products together form functional heterodimers. Digenic inheritance affects ~3% of hereditary diseases in addition to the classic autosomal and X-linked disorders.
  • mitochondrial diseases (maternal or autosomal inheritance)
  • multifactorial diseases (interaction of several to many genes plus environmental factors)

Gene panels

The following gene panels are offered; according to the candidate genes to be provided, they vary in scope and are sometimes very large:

  • Microcephaly, prenatal and/or postnatal (without additional information)
  • Prenatally abnormal limbs
  • Prenatally conspicuous nuchal translucency
  • Prenatally abnormal kidney/urinary system
  • Prenatally conspicuous corpus callosum
  • Prenatally abnormal fetus - rare syndrome?
  • Prenatally conspicuous heart
  • Prenatally conspicuous skeleton
  • Prenatal akinesia/hypokinesia
  • Prenatal anophthalmia/microphthalmia
  • Prenatal DSD (prenatal disorders of sex determination/differentiation)
  • Prenatal holoprosencephaly
  • Prenatal lissencephaly
  • Prenatal pontocerebellar hypoplasia
  • Prenatal VATER/VACTERL Association
  • Prenatal growth retardation
  • Prenatal hydrocephalus
  • Prenatal Dandy-Walker syndrome
  • Prenatal Joubert syndrome spectrum
  • Prenatal Noonan syndrome spectrum