Glossary
- Hematopoietic stem cells : The stem cells that give rise to all the blood cell types (red blood cell, white blood cell, platelets.
- Hemizygote : A male patient with an X-linked disease. Since, being male he only has one X chromosome, if one of the genes on this chromosome is abnormal, he is hemizygote for this trait.
- Heterodimer : Combination of the two molecules (dimer) which are different from each other (hetero).
- Heterozygote : Person who for a given gene has one normal allele and one mutant allele and who is therefore a carrier.
- Histology : Microscopic study of tissues in order to better understand their function and structure so as to be able to identify any eventual anomalies.
- Homozygote : An individual who has two identical alleles of the gene for a given trait. They may have two 'good' genes or two 'bad' genes.
- Hydrocephalus : Excessive cerebrospinal fluid build up around the brain ('water on the brain') with associated increase in intraventricular pressure.
- Hyperpolarization : Changes in the cell membrane potential.
- Hypertonia : Too much muscle tone leading to stiffness (Muscular hypertonia).
- Hypomyelination : Lack of myelin.
- Hypotonia : Loss of muscle tone.
- Hypoxia : Deprivation of adequate oxygen supply.