Question

Hi. I am studying Human Genetics. The subject is dwarfism.

My question is : In relation to dominant gene alleles and recessive gene alleles determine expression of single-gene traits, such as dwarfism, describe (a). the problem of dwarfism and (b) the clinical features?

Answer 1

ANSWER -

1) dwarfism is caused due to the recessive trait and when two recessive alleles comes together, they lead to this condition,ie homozygously recessive condition

for example, if we consider that there are two alleles which governs the height, the dominant one which results into tallness is represented as 'T' and the recessive one which represent dwarfness is represented by 't'

as we know that,alleles which regulate the same trait occurs in pairs, as in paired chromosomes, and the dwarfism condition will occur only and only when there will be two recessive alleles being trnsferred , ie only 't' passes to the next generation from both parents.

this condition will result into dwarf person

2) if one need to write down about dwarfism then various points are being mentioned below -

i) it is a medical or genetic condition in which the height remains less than 4feet 10 inch, and the average height of dwarf people are carried upto 4 feet

ii)it is of two types, disproportionate and proportionate, if few of the body parts are not in proper size then it is disproportionate dwarfism while, if the whole body is small in size then it is called as proportionate

iii) the most common cause of dwarfism is achondroplasia and there is another cause for dwarfism, spondyloepiphyseal,

iv) the whole body have shorter body parts, from short trunk to short limbs.

these are few of the basics of the dwarfism and how it is caused and its phenotypic symptoms and types.