Molecular genetics is a field of medicine that is inextricably linked to clinical genetics, where, based on a clinical / phenotypic suspicion of genetically determined disease (syndrome), the molecular laboratory strives to identify, at the molecular-genetic level, the causative mutation/s leading to the genetic disorder in the affected individual / family.
The laboratory approach to the patient is no different, be it human or animal, since the technology that allows for the detection of causal mutations is based on "reading" DNA, no matter if it "reads" the DNA of humans, animals, bacteria, fungi, virus or a plant. Technology interlinks the field of molecular genetics in its full complexity.
In this application, clinical geneticist invites the index individual and the family in which the affected child was born to a genetic counseling. By studying pedigrees, taking a detailed medical history, carefully studying the proband phenotype, the clinical geneticist expresses his suspicion of a particular syndromological entity and asks the laboratory for genetic analysis. In the current modern era of the availability of NGS (Next Generation Sequencing) technology, the laboratory can sequence and analyze very extensive panels of genes known to be associated with the particular syndrome. Larger NGS platforms can even sequence entire genomes in order to find a causal mutation if the primary search within known genes has not yielded the necessary information. These examinations are very expensive and should be covered by the public health system financial resources.
Due to extensive inbreeding (intra-species crossing) during the last decades, genomes (DNA) of purebred animals have been significantly polluted with biologically deleterious mutations, leading to serious genetically determined clinical diseases, handicapping or even killing the affected individuals. Genetic profiling of purebred animals, i.e. testing of animals for presence/absence of genetically determined diseases and predisposition to genetically determined exterior traits typical for individual breeds are novel options in breeding programs that become popular in developed countries. Due to its complexity, this method allows for more sensible approach to breeding both on the level of individual animals and whole breeds.
The absolute majority of pathogenic mutations in animals known to date are inherited in so called autosomal-recessive manner (AR); the carriers of the particular mutation (heterozygous individuals) cannot be recognized from their healthy peers. Nevertheless, the carriers of mutated alleles pose a significant risk to their offspring, with significant proportion of affected litter. Some genetic mutations are effective immediately after the birth and afflicted animals fail to thrive, some are severely handicapped for the rest of their lives, and some even die. Other genetic diseases manifest later in the infancy or during the adulthood and decrease significantly the well-being or the lifespan of animals. Some genetic abnormalities might even be incompatible with life and lead to abortions and stillbirth.
The aim of the “Intelligent breeding” program is the complex genetic profiling of purebred animals and their offspring to diagnose carriers of pathogenic mutations or index animals. This approach can aid the breeders in the correct selection of the mating partner for their valuable animals, based on their genetic profile and genetic health.