DNA probes are short, labelled, single-stranded DNA sequences that can identify specific alleles.

1. Probes that are radioactively labelled with an isotope that can be identified using X-rays
2. Fluorescently labelled probes that can emit light when the probe is bound to a complementary DNA sequence

1. Denaturation - DNA strands are heated, causing them to separate into two single strands
2. Fragmentation - DNA strands are digested into fragments using restriction enzymes
3. Mixing - DNA fragments are mixed with DNA probes that are marked, like with fluorescent dye
4. Hybridisation - DNA probes bind to complementary sequences on DNA strands
5. Identification - UV light is shone on fragments and those with sequences that are complementary to the DNA probes fluoresce

DNA sequencing determines the base sequence needed to create a complementary probe for a specific allele.

Genetic screening identifies individuals carrying specific alleles that may lead to genetic disorders.

During genetic screening, DNA probes bind to complementary DNA sequences in samples, indicating the presence of these specific alleles.

Personalised medicine tailors healthcare for optimal treatment based on an individual's genetic makeup.

A genetic counsellor uses genetic screening results and research into family history to advise on the likelihood of inherited diseases in offspring.

They also provide information on the possible consequences of these diseases, to help individuals make an informed decision on whether or not to have children.

Genetic screening identifies genetic predispositions, helping doctors choose effective drugs and treatment strategies.