Pronunciation: [hˌɛmɪzˈɪɡəs] (IPA) 
Hemizygous is a term often used in genetics to describe the presence of only one copy of a particular gene in a cell or organism. The word is spelled as "he-mi-zai-gus" in IPA phonetic transcription. The first syllable "he" is pronounced like the word "he" and the "mi" is pronounced like "me". The "zaigus" part is pronounced as "zi-gus", with the "zi" sounding like the "si" in "since" and the "gus" sounding like "gus" in "gust".
Hemizygous is an adjective that describes a genetic condition in which only one copy of a particular gene or chromosome is present in an individual, typically in males. Hemizygosity occurs when a gene or chromosome is either absent or inactivated on one of the sex chromosomes (usually the X chromosome in humans), leading to the individual having only a single functioning copy of that gene.
This phenomenon is primarily observed in males since they possess one X and one Y chromosome, whereas females have two X chromosomes. Due to possessing only one X chromosome, if a male inherits a recessive trait or carries a mutation on his X chromosome, he will be hemizygous for that specific trait, as it is not balanced by a second copy of the chromosome to potentially mask or counteract the effect. This could make the male more susceptible to certain genetic disorders or conditions that are linked to genes on the X chromosome.
The term "hemizygous" is commonly used in the field of genetics to describe the unique genetic makeup of males and the specific consequences of possessing a single copy of particular genes or chromosomes. It helps researchers and geneticists understand the inheritance patterns and characteristics associated with genes located on the X chromosome, aiding the diagnosis and study of genetic disorders.
The word "hemizygous" is derived from the combination of two Greek roots: "hemi" which means "half" and "zygous" which means "yoked" or "paired". "Zygous" itself is derived from "zygon" meaning "yoke". When these two roots are combined, "hemizygous" conveys the idea of being only partially paired or having only half a set of paired chromosomes. The term is commonly used in genetics to describe an individual carrying only one allele for a given gene when it would normally be present in the paired form.
