This information has been designed to give a brief overview of what a skin biopsy is, how it is done and why it is a useful test. If you have any questions or if you would like to discuss anything in further detail, please feel free to ask your genetics doctor or counsellor.

What is a skin biopsy?

A skin biopsy is the removal of a small piece of skin, usually from a person’s forearm.

Why may a skin biopsy be useful?

Skin biopsies can help us make or rule out a diagnosis.

Consent and skin biopsy

Before you have a skin biopsy taken it is important that you understand what the procedure involves, what will happen to your skin sample, how you will be given the result of the test and what the implications of the test result might be. We need your written permission to perform a skin biopsy and your agreement is called consent.

How is a skin biopsy taken?

Skin biopsies are usually done using local anaesthetic. It is not a painful procedure.

It takes about 10 minutes to perform. A doctor will perform the procedure.

• The skin is cleaned with antiseptic.
• A small amount of anaesthetic is applied to or injected into the skin to numb it.
• When the skin is numb a small circle of skin (3-4mm, less than a quarter the size of your little fingernail) is cut using a tool similar to a hole punch.
• The sample of skin is separated from the rest of the skin with a small scalpel and sent for analysis.
• Pressure is then applied to the site of the biopsy until the bleeding stops. Stitches are not usually required.
• A dressing is then applied.
• The area should be kept dry for 24 hours and then the dressing can be taken off after 2 or 3 days.

What are the complications?

The skin may begin to bleed again and require a fresh dressing.

here will be a small scar where the biopsy was taken. This is usually red at first and, with time, fades to a white colour.

What happens to the sample of skin once it has been taken?

The skin sample is put into some fluid that contains ingredients necessary to keep the skin cells alive. The sample of skin is then grown in a small plastic flask in our laboratory. Occasionally the skin cells fail to grow and a repeat sample is needed.

The laboratory can look at:

• The chromosomes in the skin cells
• The structure of the skin
• How the skin cells function

Some of the skin cells will be frozen and stored in case further tests become possible. The stored skin cells would not be given to anyone else without your permission. Skin cells may also be used anonymously as part of the national scheme for quality assurance in NHS genetics laboratories.

When will I get my results?

As it takes time to grow the skin cells in our laboratory and perform specialised tests, it is usually about two months before the results are available. Sometimes skin cells are sent to other laboratories, and in this case it may be longer before results are available.

How will I be given the results?

This will be agreed with you at the time of the test. Your result will be treated in strict confidence and will not be given to anyone else unless you have given permission.

We are always happy to receive comments

Please direct all enquiries to:

Northern Genetic Service
Institute of Human Genetics
Central Parkway
Newcastle upon Tyne
NE1 3BZ
Tel: 0191 241 8600 [8.30am – 5.00pm Monday to Friday]
Fax: 0191 241 8799