118. Haemoglobinopathies : Medical Biochemistry | USMLE, FMGE and NEET PG

๐’๐ฎ๐›๐ฌ๐œ๐ซ๐ข๐›๐ž ๐—™๐จ๐ซ ๐— ๐จ๐ซ๐ž ๐—œ๐ง๐Ÿ๐จ๐ซ๐ฆ๐š๐ญ๐ข๐จ๐ง ๐จ๐ง ๐—›๐ž๐š๐ฅ๐ญ๐ก ๐Ÿ‘ฉโ€โš•โ€ ๐š๐ง๐ ๐— ๐ž๐๐ข๐œ๐ข๐ง๐ž๐Ÿ’‰๐Ÿฉบ๐Ÿ’Š ๐˜๐จ๐ฎ๐ญ๐ฎ๐›๐ž : ย ย ย /ย @draishwaryakelkarย ย  ๐Ÿ“Œ๐—™๐—ฎ๐—ฐ๐—ฒ๐—ฏ๐—ผ๐—ผ๐—ธ : ย ย /ย draishwaryakelkarย ย  ๐Ÿ“Œ๐—ง๐˜„๐—ถ๐˜๐˜๐—ฒ๐—ฟ: ย ย /ย aishwayadrย ย  ๐Ÿ“Œ๐—œ๐—ป๐˜€๐˜๐—ฎ๐—ด๐—ฟ๐—ฎ๐—บ : ย ย /ย clinical.learningย ย  Haemoglobinopathies are inherited disorders of globin, the protein component of haemoglobin (Hb). Mutations in genes coding for the globin proteins that alter protein output produce the thalassaemia syndromes. Mutations in the globin genes that lead to abnormal proteins are called variant Hbs. Haemoglobinopathies are the commonest genetic defect worldwide with an estimated 269 million carriers. Certain populations are particularly at risk of having a haemoglobinopathy, for example, in South East Asia, there are 90 million carriers, about 85 million in sub-Saharan Africa and 48 million in the West Pacific region. The thalassaemia syndromes and some of the Hb Variants are inherited as autosomal recessive conditions. Very rarely, ฮฒ thalassaemia demonstrates an autosomal dominant inheritance pattern. Some Hb Variants also have an autosomal dominant inheritance pattern, while others can occur spontaneously. There are many genes coding for the globins. They are found on chromosome 11 (ฮฒ globin cluster) or chromosome 16 (ฮฑ globin cluster). For the purpose of this review, the important globin genes in humans are the 2 ฮฒ globin genes and the 4 ฮฑ globin genes. Despite different numbers of ฮฑ and ฮฒ globin genes, the net ฮฑ/ฮฒ globin protein output from these genes is balanced to give a ratio of 1 #haemoglobin #Haemoglobinopathies #globins #thalassaemia #genes #medicalstudents #mbbs #biochemistry #chemistry