If genetic material from another species is added to the host, the resulting organism is called transgenic. If genetic material from the same species or a species that can naturally breed with the host is used, the resulting organism is called cisgenic.

A nonsense mutation is a point mutation in a sequence of DNA that results in a premature stop codon, or a nonsense codon in the transcribed mRNA, and possibly a truncated, and often nonfunctional protein product.

The cause of Tay–Sachs disease is a genetic defect that is passed from parent to child. This genetic defect is located in the HEXA gene, which is found on chromosome 15. The HEXA gene makes part of an enzyme called beta-hexosaminidase A, which plays a critical role in the nervous system.

Specificity factors alter the specificity of RNA polymerase for a given promoter or set of promoters, making it more or less likely to bind to them, i.e. sigma factors used in prokaryotic transcription.

HIV infection is due to transmission of the HIV virus, not the antibody. However, the presence of maternal anti-HIV IgG can lead to diagnostic difficulty. It is therefore necessary to confirm HIV infection in the newborn by the presence of viral DNA or RNA using a polymerase chain reaction (PCR) method.

In humans, the inherited causes account for 50% of all cases of severe sensorineural hearing impairment and 80% are due to single-gene autosomal recessive disorders.

Silent mutations codes for the same amino acid. A silent mutation has no effect on the functioning of the protein. A single nucleotide can change, but the new codon specifies the same amino acid, resulting in an unmutated protein.

The umbilical artery caries used blood away from the fetus and so the pH can never be higher than in the vein.

Nuclear Run-on assay measures the relative abundance of newly formed transcripts.

It is important to monitor congenital abnormalities to understand their aetiology. Preconception folic acid supplementation to prevent spina bifida shows the benefit of recognizing high-risk groups.

Gene expression profiling is the measurement of the activity of thousands of genes at once, to create a global picture of cellular function. These profiles can, for example, distinguish between cells that are actively dividing, or show how the cells react to a particular treatment.

This increases the risk of monochorionic monoamniotic (MCMA) twins by 5 times.

Thomas Bourgeron discovered the first monogenic mutations involved in autism.

Pregnancies that share the placenta and amnion are at highest risk of adverse outcome because of risk of twin-to-twin transfusion syndrome and cord entanglement.

Robertsonian translocation is a type of reciprocal translocation caused by breaks at or near the centromeres of two acrocentric chromosomes. The reciprocal exchange of parts gives rise to one large metacentric chromosome and one extremely small chromosome that may be lost from the organism with little effect because it contains so few genes.